Back in the old days I bought a NES to play TEENAGE NINJA TURTLES 3, I used to love that game, but I actually want a console for all the games, not a particular one.
SNES: I really wanted to play Super Mario World, that game even smelled good for me as a kid, weird, but it did, the game had a smell...
PSone: Silent Hill and resident Evil. These games made me go back to gaming after a 2 years hiatus.
PS2: silent hill 2 and 3, I had to have another fix of horror =D
Xbox 360: Fallout 3 for sure, it was awesome.
PS3: Uncharteds and MGS4, it was too much to resist.
PSP: Silent Hill origins, but I never liked handhelds that much.
PSVita: Uncharted Golden something, not really worth it =/
3DS: Super Mario 3d land: not really worth it =/
I did bought a XBOX ONE to play Dead Rising 3 and, man, for now, it is the only exclusive that I would really consider a must have, it is amazing, it has a b-movie feel to it, like a cult cool horror classic, like Return of the Living Dead or something like that.
I bought, in other hand, the PS4 for the system, not for any game in particular, but it does have some cool games: Killzone, Infamous, Watch Dogs, Dont Starve, Lego Marvel, Outlast, Stick to the man...
However, I still want to buy a WiiU to play zombiU, it would be soooooo cool if they release it for PS4, it would save me a lot of money.