For those with a PS3, if you subscribe to Playstation Plus ($17.99/3 months) you can download some pretty new, full titles for free:
Warhammer 40k: Space Marine
Just Cause 2
Saints Row 2
Lara Croft and the Guardian of Light
Ratchet and Clank All 4 One
Even if you were to buy all of these games used you still be looking at over $100. Pretty sweet deal. You also get things like cloud saves and access to some other free crap.