Id be surprised if COD4 was about to go away whats that? definately recommend the Half Life Series - Half Life,Opposing Force,Blueshift,Decay,HL2,HL2e1,HL2e2 or you could wait for black mesa source which is an awesome looking remake of HL1 I cant help but sort of disagree and say that my oppinoin is that you should only play the original because it is better then the sequals. and ofcourse UT99 has Strangelove which is awesome So yeah definately orange box should keep you busy for a couple of days till you need some more games or you could play The Hell, a mod for the Hellfire expansion to Diablo I apparently that has a lot of game time on the hardest difficulty, think of it as preperation for Diablo III