DS (2005): No game in particular. It just looked cool. (First game was "Feel the Magic")
360 (2007): Unable to find a PS3 and I wasn't going home empty handed. (First game was "Kameo")
Wii (2007): No game in particular. Saw one in store and couldn't believe it. (First game was "Resident Evil: Wii Edition")
PS3 (2008): Metal Gear Solid 4
PSP (2009): Wanted to watch movies while I "worked" at my new job. (First game was "Rainbow 6: Vegas").