Halo 2 for Xbox. I had been gaming for a good 6 years before, but only on Nintendo Gamecube and on the Gameboy Advance. I wasn't really a "gamer", just someone who occasionally played games. My next door neighbour however, assured me that a I had not played a truly amazing game: Halo 2. He lent me his Xbox with Halo 2 and I played the campaign over a 2 day weekend. I was unbelievably amazing. I had never seen such good graphics, never held such a great controller, and never really played a "modern shooter" before (other than CoD3 on my PS2 but I still played that casually). It was the only reason I even bought a 360 in the first place (although I still bought the Wii first). SO thanks Bungie, thank you for inspiring me to become a gamer.