For a top 10, I'd say:
1. SNES;
2. N64;
3. GCN;
4. DC;
5. NES;
6. ....
Errr, I can't really choose for the rest between Xbox 360, Wii, PS2, PSX and Genesis. PS3 will definitely go up in the list once it gets more games that really defines the console for itself (LittleBigPlanet is a big step). ;)
*EDIT: Oh, apparently I have to list all the consoles I own? OK, here goes nothing:
-Very old stuff: Commodore VIC-20 (lol, Gorf rocked!!!);
-Nintendo: NES, Gameboy, SNES, Gameboy Color, N64, GameCube, GBA, GBA SP, DS, Wii;
-Sega: Genesis, Saturn, Dreamcast;
-Sony: PlayStation, PlayStation 2, PlayStation 3;
-Microsoft: Xbox 360.
I don't think I'm missing one right now...