I'm a fan of a LOT of slash, so here's my list (all canon or semi-canon: creators admit to adding LOTS of hints):
Top 10: 1. Luke/Jon (The Living End)
2. McDean (JP/Craig Hollyoaks)
3.Fraser/RayK (Due South)
4. Jack/Ianto (Torchwood)
5. Hilson (House/Wilson)
6. Walter/Jarvis (Wilby Wonderful)
7. Yukito/Touya (SCC, my first)
8. James/Donald (Our Sons)
9. Lupin/Sirius
10. Matt/Brian (The Event)
Mark/Scott (Save Me)
Joe/Billy (Hard Core Logo)
Angel/Spike (Angel)
Jack/John (Torchwood)
Mark/Alex (As If)
Ted/Emmett (QAF)
Deniz/Roman
Max/Iago (El Cor de la cuitat)
Donner/John (Johns)
Matthew/Theo (The Dreamers)
Tony/Maxxie (Skins)
Tony/Syd
Christian/Aaron (Latter Days)
Mulder/Krycek (X-Files)
Bayliss/Kellerman (H:LotS)
Jimmy/Coop (Cold Case)
Martin/Tom (Hollow Reed)
Cliff/Butch (Sugar)

Non-canon: BJ/Hawkeye (MASH)
Mylar (Heroes)
Petrillicest
RyCol (Ryan/Colin from WLIIA?)
Rocky/Marty (Mean Creek)
Master/Doctor (Doctor Who)
McShep (LOVE!)