Wii - Resident Evil 4
360 - Resident Evil 5 (in 2009)
PS3 - resident Evil 6 (in 2011) :)

PS3 - Final Fantasy XIII, White Knight Chronicles, Metal Gear Solid 4
XBOX360 - Fable 2, Lost Odyssey, Infinite Undiscovery
Wii - Monster Hunter 3, SSMB, Dragon Quest IX

Wii: SMG SSBB & Zelda

I own the other two, so meh.

PS3 - MGS4, FFXIII, Gt5

Wii - Wii Fit, SSBB, SMG

360 - Fable 2, ME, COD4

The holy trinity: Wii: Ninja Bread Man
Chicken Shoot
Cruis'n


But since that's asking too much, I'd say Prime 3, Mario Galaxy, and Wario Smooth Moves.

Wii - Super Mario Galaxy, SSBB, LoZ:TP
PS3 - Gran Turismo 5, Motorstorm: Pasifica, Resistance 2
Xbox 360 - Halo 3, PGR4, CoD4

Wii: Super Mario Galaxy, Super Smash Bros Brawl, Zelda: Twilight Princess.

PS3: The Orange Box, Call of Duty 4, Assassins Creed.

X360: Halo 3, Mass Effect, Bioshock.

Green = Have.

Red = Don't have.

GTA-FF-GT

Wii: SMG, SSBB and MKWii
PS3: GTA, GT and FF.
X360: COD4, Halo 3 and Gears of War.

WII - SSBB , Mario Kart wii
PS3 - MGS4,,GT5p
360 - Halo 3, GoW2