This list of crossover pairings/scenarios was compiled from the unfulfilled requests sent in by participants in the ficathon. (And a couple I chucked in for fun, to bring it up to a nice round number.) The slashes and ampersands (that's the & symbol, indicative here of a relationship that's not romantic/sexual) are only suggestions. If a scenario with a / turns out to be ampersand or a scenario with a & turns into slash or het, no problem. Send it in anyway. There are no minimum length requirements, ratings restrictions or time limits on these either.
Also, participants in the original ficathon should feel free to write requests they originally submitted.
1. Bialar Crais (Farscape)/Alfred Bester (Babylon 5)
2. Mal Reynolds (Firefly)/Kathryn Janeway (Star Trek: Voyager)
3. River Tam (Firefly) & The Heart of Gold (Hitchhiker's Guide to the Galaxy)
4. Mele-On Grayza (Farscape)/Servalan (Blake's 7)
5. Simon Tam (Firefly)/River Tam (Firefly)/Lennier (Bablyon 5)
6. Kosh (Babylon 5) & Q (Star Trek)
7. Arthur Dent (Hitchhiker's Guide to the Galaxy)/Dave Lister (Red Dwarf)
8. Kaylee Frye (Firefly)/Teal'c (Stargate SG-1)
9. Vir Cotto (Babylon 5) & Star Trek: Deep Space Nine, Bajoran Occupation time frame.
10. Kara Thrace (New Battlestar Galactica)/Aeryn Sun (Farscape)
11. Susan Ivanova (Babylon 5)/Pavel Chekov (Star Trek)
12. Roj Blake (Blake's 7) & Farscape
13. Mal Reynolds (Firefly)/Han Solo (Star Wars)
14. Scorpius (Farscape)/Lyta Alexander (Babylon 5)
15. Jake Sisko (Star Trek: Deep Space Nine) & Firefly
16. Padme Amidala (Star Wars)/Zev (Lexx)
17. Tyr Anasazi (Andromeda)/Seven of Nine (Star Trek: Voyager)
18. Jean-Luc Picard (Star Trek: The Next Generation) & Babylon 5
19. Jack O'Neill (Stargate SG-1)/Daniel Jackson (Stargate SG-1)/Julian Bashir (Star Trek: Deep Space Nine)
20. Scorpius (Farscape)/River Tam (Firefly)
21. Zoe Warren (Firefly) & Hitchhiker's Guide to the Galaxy
22. Chiana (Farscape)/T'Pol (Star Trek: Enterprise)
23. Leia Organa (Star Wars)/Teal'c (Stargate SG-1)
24. Aeryn Sun (Farscape) & Space: Above and Beyond
25. Ford Prefect (Hitchhiker's Guide to the Galaxy)/Nerri (Farscape)
26. Odo (Star Trek: Deep Space 9)/Cally (Blake's 7)
27. Obi-Wan Kenobi (Star Wars) & Scorpius (Farscape)
28. Kaylee Frye (Firefly)/Sam Carter (Stargate SG-1)
29. Jack O'Neill (Stargate SG-1)/Kira Nerys (Star Trek: Deep Space Nine)
30. The Fourth Doctor (Doctor Who) & Star Wars
31. Bialar Crais (Farscape)/Travis (Blake's 7)
32. Dureena Nafeel (Crusade)/James T. Kirk (Star Trek )
33. Star Wars & Hitchhiker's Guide to the Galaxy
34. Delenn (Babylon 5)/Inara Serra (Firefly)
35. Daniel Jackson (Stargate SG-1)/Rommie (Andromeda)
36. The Doctor (Doctor Who) & Stargate SG-1
37. Qui-Gon Jinn (Star Wars)/Jacob Carter (Stargate SG-1)
38. John Crichton (Farscape)/Original Ripley (Alien). Double points for both Johns.
39. Kerr Avon (Blake's 7)/Data (Star Trek: The Next Generation)
40. Servalan (Blake's 7)/Saffron (Firefly)
41. Trip Tucker (Star Trek: Enterprise)/Kaylee Frye (Firefly)
42. Marvin the Paranoid Android (Hitchhiker's Guide to the Galaxy) & Paranoia (Red Dwarf)
43. Daniel Jackson (Stargate SG-1)/John Crichton (Farscape)
44. Simon Tam (Firefly)/Chiana (Farscape)
46. Data (Star Trek: The Next Generation) & C3PO (Star Wars)
47. Julian Bashir (Star Trek: Deep Space 9)/Mal Reynolds (Firefly)
48. Han Solo (Star Wars)/Susan Ivanova (Babylon 5)
49. Jean-Luc Picard (Star Trek: The Next Generation) & Blake's 7
50. Dylan Hunt (Andromeda)/Kathryn Janeway (Star Trek: Voyager)/John Sheridan (Babylon 5)/Aeryn Sun (Farscape)/Mal Reynolds (Firefly)/Janet Fraiser (Stargate SG-1)/Luke Skywalker (Star Wars)/Ellen Ripley (Alien)
51. Kosh (Babylon 5)/Thor (Stargate SG-1)
52. Daniel Jackson (Stargate SG-1)/Saffron (Firefly)
53. James T. Kirk (Star Trek ) & Alfred Bester (Babylon 5)
54. Seven of Nine (Star Trek: Voyager)/Kara Thrace (New Battlestar Gallactica)
55. Aeryn Sun (Farscape)/Jack O'Neill (Stargate SG-1)
56. Trance (Andromeda) & Babylon 5
57. General Martok (Star Trek: Deep Space Nine)/Bra'tac (Stargate SG-1)
58. Jean-Luc Picard (Star Trek: The Next Generation)/Catherine Sakai (Babylon 5)
59. Q (Star Trek) & Lorien (Babylon 5)
60. Susan Ivanova (Babylon 5)/Sikozu (Farscape)/Sam Carter (Stargate SG-1)
61. Bekka Valentine (Andromeda)/Mal Reynolds (Firefly)
62. Scorpius (Farscape) & Spock (Star Trek )
63. Alastair Gordon Lethbridge Stewart (Dr. Who)/Scotty (Star Trek )
64. Kathryn Janeway (Star Trek: Voyager)/Jack O'Neill (Stargate SG-1)
65. Londo Mollari (Babylon 5) & Star Trek: Deep Space Nine
66. Rommie (Andromeda)/Padme Amidala (Star Wars)
67. Leia Organa (Star Wars)/Dave Lister (Red Dwarf)
68. Jake Sisko (Star Trek: Deep Space 9) & G'Kar (Babylon 5)
69. Daniel Jackson (Stargate SG-1)/Mal Reynolds (Firefly)
70. Teal'c (Stargate SG-1)/Kira Nerys (Star Trek: Deep Space 9)
71. John Crichton (Farscape) & Battlestar Galactica
72. Leela (Dr. Who)/Cally (Blake's 7)
73. Kara Thrace (New Battlestar Gallactica)/Jayne Cobb (Firefly)
74. Yoda (Star Wars) & Vir Cotto (Babylon 5)
75. Ford Prefect (Hitchhiker's Guide to the Galaxy)/Daniel Jackson (Stargate SG-1)
76. G'Kar (Babylon 5)/Kira Nerys (Star Trek: Deep Space 9)
77. Kryten (Red Dwarf) & The Doctor (Star Trek: Voyager)
78. Sam Carter (Stargate SG-1)/B'Elanna Torres (Star Trek: Voyager)
79. Jayne Cobb (Firefly)/Kaylee Frye (Firefly)/Han Solo (Star Wars)
80. D'Argo (Farscape) & G'Kar (Babylon 5)
81. Grey Council (B5)/Jedi Council (Star Wars)
82. Kira Nerys (Star Trek: Deep Space 9)/Kerr Avon (Blake's 7)
83. Andromeda & Stargate SG-1
84. Zoe Warren (Firefly)/Aeryn Sun (Farscape)/Seven of Nine (Star Trek: Voyager)
85. The Doctor (Doctor Who)/Sam Carter (Stargate SG-1)
86. Scorpius (Farscape) & Elim Garak (Star Trek: Deep Space 9)
87. D'Argo (Farscape)/Teal'c (Stargate SG-1)
88. Chiana (Farscape)/Jayne Cobb (Firefly)
89. Psi Corps (Babylon 5) & Peacekeeper High Command (Farscape)
90. Inara Serra (Firefly)/Leia Organa (Star Wars)
91. Cally (Blake's 7)/Daniel Jackson (Stargate SG-1)
92. Arthur Dent (Hitchhiker's Guide to the Galaxy) & John Crichton (Farscape)
93. Quark (Star Trek: Deep Space 9)/Sam Carter (Stargate SG-1)
94. Thor (Stargate SG-1)/Q (Star Trek)
95. Shane Vansen (Space: Above And Beyond)/Jack O'Neill (Stargate SG-1)
96. Luke Skywalker (Star Wars) & Data (Star Trek: The Next Generation)
97. River Tam (Firefly)/T'Pol (Star Trek: Enterprise)
98. Deanna Troi (Star Trek: The Next Generation)/Jonas Quinn (Stargate SG-1)
99. Sikozu (Farscape) & Doctor Who
100. Arnold Rimmer (Red Dwarf)/Miklo Braca (Farscape)
101. Dax (Star Trek: Deep Space Nine)/Stark (Farscape)/Zhaan (Farscape)
102. Jack O'Neill (Stargate SG-1) & Zaphod Beeblebrox (Hitchhiker's Guide to the Galaxy)
103. Jenna Stannis (Blake's 7)/Romana II (Doctor Who)
104. Londo Mollari (Babylon 5) & Teal'c (Stargate SG-1)
105. Bekka Valentine (Andromeda) & River Tam (Firefly)
106. Harvey (Farscape)/Kosh (Babylon 5)
107. Jack Harkness (Doctor Who)/Chiana (Farscape)
108. Q (Star Trek) & Blake's 7
109. Ellen Ripley (Alien)/Jadzia Dax (Star Trek: Deep Space Nine)
110. Kryten (Red Dwarf) & Data (Star Trek: The Next Generation)
111. Shepherd Book (Firefly) & Obi-Wan Kenobi (Star Wars) & Star Trek: The Original Series
112. Rodney McKay (Stargate: Atlantis)/Vila Restal (Blake's 7)/Kerr Avon (Blake's 7)
113. Bialar Crais (Farscape)/Dayna Mellanby (Blake's 7)
114. Daniel Jackson (Stargate: SG-1) & Farscape
115. Susan Ivanova (Babylon 5)/Zoe Warren (Firefly)
116. Laura Roslin (New Battlestar Galactica)/Lennier (Babylon 5)
117. The Second Doctor (Doctor Who) & Spock (Star Trek)
118. Julian Bashir (Star Trek: Deep Space Nine)/Malcolm Reed (Star Trek: Enterprise)/Gaius Baltar (New Battlestar Galactica)
119. Laura Roslin (New Battlestar Galactica) & Servalan (Blake's 7)
120. Vir Cotto (Babylon 5) & Stark (Farscape) & Vila Restal (Blake's 7)
121. Number Six (New Battlestar Galactica)/Seven of Nine (Star Trek: Voyager)
122. River Tam (Firefly) & Sharon Valerii (New Battlestar Galactica)
123. The Doctor (Star Trek: Voyager) & Red Dwarf
124. Gaeta (New Battlestar Galactica)/Miklo Braca (Farscape)
125. Jack Harkness (Doctor Who)/Jenna Stannis (Blake's 7)
126. Rodney McKay (Stargate: Atlantis) & Sikozu (Farscape)
127. Trance (Andromeda)/Kaylee Frye (Firefly)
128. Yoda (Star Wars) & Dave Lister (Red Dwarf) & Blake's 7
129. Marvin the Paranoid Android (Hitchiker's Guide to the Galaxy) & R2D2 (Star Wars) & C3PO (Star Wars)
130. Miles Vorkosigan (Miles Vorkosigan)/Marcus Cole (Babylon 5)
131. Number Six (Battlestar Galactica)/The Fourth Doctor (Doctor Who)
132. Inara Serra & Jean-Luc Picard (Star Trek: The Next Generation)
133. John Sheppard (Stargate: Atlantis)/Lee Adama (New Battlestar Galactica)
134. Seven of Nine (Star Trek: Voyager) & Kerr Avon (Blake's 7)
135. Bialar Crais (Farscape) & Kosh (and/or his ship) (Babylon 5)
136. Jack Harkness (Doctor Who)/Mal Reynolds (Firfly)
137. B'Elanna Torres (Star Trek: Voyager) & Zoe Warren (Firefly)
138. Sikozu (Farscape) & Battlestar Galactica
139. Kara Thrace (New Battlestar Galactica)/Kira Nerys (Star Trek: Deep Space Nine)
140. Q (Star Trek) & Miles Vorkosigan (Mikes Vorkosigan)
141. Mal Reynolds (Firefly) & Kara Thrace (New Battlestar Galactica)
142. Gaius Baltar (New Battlestar Galactica)/John Crichton (Farscape)
143. Trip Tucker (Star Trek: Enterprise)/T'Pol (Star Trek: Enterprise)/Teal'c (Stargate: SG-1)
144. Miles O'Brien (Star Trek: Deep Space Nine) & Tyrol (New Battlestar Galactica)
145. Lyta Alexander (Babylon 5)/Number Six (New Battlestar Galactica)
146. Winn Adami (Star Trek: Deep Space Nine) & Laura Roslin (New Battlestar Galactica)
147. Spock (Star Trek: The Original Series) & Marvin the Paranoid Android (Hitchiker's Guide to the Galaxy)
148. Mal Reynolds (Firefly)/John Crichton (Farscape)
149. Simon Tam (Firefly)/Teyla (Stargate: Atlantis)
150. Elim Garak (Star Trek: Deep Space Nine) & Kerr Avon (Blake's 7)
151. Deanna Troi (Star Trek: The Next Generation)/Kathryn Janeway (Star Trek: Voyager)
152. Han Solo (Star Wars) & Battlestar Galactica
153 Kara Thrace & Lee Adama (Battlestar Galactica) & Aliens
154. Lee Adama (New Battlestar Galactica)/Mal Reynolds (Firefly)
155. G'Kar (Babylon 5)/Inara Serra (Firefly)
156. John Crichton (Farscape) & Sharon Valerii (Battlestar Galactica)
157. Laura Roslin (New Battlestar Galactica)/Kathryn Janeway (Star Trek: Voyager)
158. Matthew Gideon (Crusade)/Kira Nerys (Star Trek: Deep Space Nine)
159. Rodney McKay (Stargate: Atlantis) & the Minbari (Babylon 5)
160. Jack Harkness (Doctor Who)/Han Solo (Star Wars)
161. Jack O'Neill (Stargate: SG-1)/Saffron (Firefly)
162. Leia Organa (Star Wars) & Leonard McCoy (Star Trek)
163. River Tam (Firefly)/Chiana (Farscape)
164. Kara Thrace (New Battlestar Galactica)/Del Tarrant (Blake's 7)
165. Sarah Jane Smith (Doctor Who) & Leia Organa (Star Wars)
166. Jack O'Neill (Stargate: SG-1)/John Sheppard (Stargate: Atlantis)
167. Miles Vorkosigan (Miles Vorkosigan)/Chiana (Farscape)
168. Stark (Farscape) & River Tam (Firefly)
169. Aeryn Sun (Farscape)/Zoe Warren (Firefly)
170. Tyr Anasazi (Andromeda) & Jayne Cobb (Firefly)
171. Londo Mollari (Babylon 5) & Rygel (Farscape)
172. Wesley Crusher (Star Trek: The Next Generation)/Marvin the Paranoid Android (Hitchhiker's Guide to the Galaxy)
173. Soolin (Blake's 7)/Jack O'Neill (Stargate: SG1)
174. Michael Garabaldi (Babylon 5) & Saul Tigh (New Battlestar Galactica)
175. Leia Organa (Star Wars)/Kara Thrace (New Battlestar Galactica)
176. Rodney McKay (Stargate: Atlantis) & New Battlestar Galactica
177. Q (Star Trek) & The Ninth Doctor (Doctor Who)
178. Arnold Rimmer (Red Dwarf)/Vislor Turlough (Doctor Who)
179. Luke Skywalker (Star Wars)/River Tam (Firefly)
180. Laura Roslin (New Battlestar Galactica) & G'Kar (Babylon 5)
181. Jool (Farscape)/Seven of Nine (Star Trek: Voyager)
182. John Sheppard (Stargate: Atlantis) & Aeryn Sun (Farscape)
183. Benjamin Sisko (Star Trek: Deep Space Nine) & Daniel Jackson (Stargate: SG-1)
184. The Ninth Doctor (Doctor Who)/Daniel Jackson (Stargate SG-1)
185. Rodney McKay (Stargate: Atlantis)/Sam Carter (Stargate: SG-1) & Firefly
186. Kara Thrace (New Battlestar Galactica) & Nietzchian infested Earth (Andromeda)
187. Rose Tyler (Doctor Who)/Jadzia Dax (Star Trek: Deep Space Nine)
188. Laura Roslin (New Battlestar Galactica) & John Sheridan (Babylon 5) & Delenn (Babylon 5)
189. Han Solo (Star Wars) & Daniel Jackson (Stargate: SG-1)
190. Luke Skywalker (Star Wars)/Han Solo (Star Wars) / or & Elim Garak (Star Trek: Deep Space Nine)/Julian Bashir (Star Trek: Deep Space Nine)
191. Jack Harkness (Doctor Who)/Jadzia Dax (Star Trek: Deep Space Nine)
192. James T. Kirk (Star Trek) & William Adama (New Battlestar Galactica)
193. Shane Vansen (Space: Above and Beyond)/Susan Ivanova (Babylon 5)
194. Londo Mollari (Babylon 5) & Gaius Baltar (New Battlestar Galactia)
195. Aeryn Sun (Farscape) & Sam Carter (Stargate S-G1) & Zoe Warren (Firefly) & Kira Nerys (Star Trek: Deep Space Nine) & Kara Thrace (Battlestar Galactica) & Ellen Ripley (Alien)
196. The Ninth Doctor (Doctor Who)/Seven of Nine (Star Trek: Voyager)
197. Sharon Valerii (New Battlestar Galactica)/Daniel Jackson (Stargate: SG1)
198. Rygel (Farscape) & Chiana (Farscape) & Marvin the Paranoid Andriod (Hitchiker's Guide to the Galaxy) & Ford Prefect (Hitchhiker's Guide to the Galaxy)
199. Barrayar (Miles Vorkosigan) & Stargate SG-1
200. Lyta Alexander (Babylon 5)/Mal Reynolds (Firefly)