I thought it would be nice to track how far along I've got in my self-imposed mission to write the Sixth Doctor with every other character, or at least every companion. Not urgently; it just seems to be happening anyway so I might as well make a list of it. Actually, if you have any prompts for any of these combinations, why not drop them here and I might write them! 

1. Six & Susan
2. Six & Barbara
3. Six & Ian
4. Six & Vicki - A Sensible Solution
5. Six & Steven
6. Six & Sara
7. Six & Katarina
8. Six & Dodo
9. Six & Polly
10. Six & Ben
11. Six & Jamie
12. Six & Victoria
13. Six & Zoe
14. Six & Liz
15. Six & the Brig
16. Six & Jo
17. Six & Sarah Jane
18. Six & Leela
19. Six & Romana - Never Too Late (well... it's a Colin Baker Doctor and a Lalla Ward Romana)
20. Six & Adric
21. Six & Nyssa
22. Six & Tegan
23. Six & Turlough - Lost and Found (technically)
24. Six & Peri - many, many fics
25. Six & Evelyn - multiple fics
26. Six & Flip & Constance - ...I Can Do Better
27. Six & Mel - multiple fics
28. Six & Ace - Telepathic Self-Defense for Humans
29. Six & Grace - Goodbye, Hello
30. Six & Charley - multiple fics
31. Six & Rose
32. Six & Jack
33. Six & Martha - Vicarious
34. Six & Donna
35. Six & Amy
36. Six & Rory
37. Six & River - Stand and Deliver, XOXO
38. Six & Clara - Cake Fail, Untying the Knot
39. Six & Bill
40. Six & Yaz - Bubble
41. Six & Ryan
42. Six & Graham
43. Six & Dan
44. Six & Ruby
45. Six & Belinda

Other characters

46. Six & Iris Wildthyme - The Sound of Ms Iris Wildthyme (3SF)
47. Six & Emilia Rumford - Masquerade