Need to know what games you like to tailor my recs, but you can never go wrong with Brawl, Galaxy, and Corruption, amongst many others.
Zak and Wiki is amazing (and very cheap), but you have to like point-n-clicks AND puzzlers to enjoy it, as it's a mash-up of both.
Tons of folks like No More Heroes but I, sadly, am not amongst them. Still, if you're into beat-em-ups, it SHOULD satsify you.
So, tell us what you like/play (genres AND favorite individual games), as well as what type of gaming you're interested in (pick-up-and-play? Long+epic? Single-player? Two-player co-op? Online competitive? Four player multi? With the family? Etc.). ALL of these can be accomodated by now, but we need to know what you're looking for to send you the right way.