My tips for addictive iP(roductnamehere) games
big games
Need For Speed Undercover (because any NFS game is awesome)
Dungeon Hunter, Dungeon Hunter 2 (RPG, always good)
Myst (nostalgic game is... nostalgic)
Tower Madness (endless fun)
small games
FlightControl (because you've always wanted to land planes yourself)
Trainyard (fun puzzling game)
Unblock Me (nostalgic puzzling game)
Songpop Free (test your music knowledge with this Facebook-linked game)
Angry Birds (because any other iP(roductnamehere) owner wants to know if you've beat them all)
Paper Toss (the game you've practiced on co-workers during the day is now also available after working hours)