I cant say that I have ever played the original Bioshock or any of its sequels. The latest offering is set to feature a new mode called '1999'. It's said to be a brutaly hard mode based on games when they where real games (1999) and not the console based tosh that we are so frequently served up with today. Hurrah!!!
It will probably turn out just to be console based rubbish with a proper difficulty mode but at least it's a step in the right direction.

If you are looking for a challenge from a more modern FPS game, try the COD: World At War campaign on Veteran difficulty.  Just be ready to die....alot.  It requires lighting quick reflexes and a ton of patience, but you should finish....eventually.  I almost cried when I finished this nightmare on Vet :'(

Duke Nukem Forever also serves up an old school spanking on the higher difficulties. Even easy on DNF can be a challenge.

If that isn't enough, try Ninja Gaiden 2 on xbox 360.  That will serve you up an old school fighting game style a$$ whooping like you've never seen before.  30 minutes of that will have you wanting to take the game disk and throw it at the wall like a ninja star.  No, I haven't finished this one, but it's in my backlog of games.

If realism is your bag, try Red Orchestra 2.  This game shows you just how real actual war can be.  I felt humbled after playing the first few missions of the campaign.

 

Call of duty 4 was enjoyable, but the next one was utter rubbish. Set in on veteran and get 6 grenades thrown at you at the same time by unseen enemies while you'r in a trench. Might as well have the jap soldiers throwing pianos at you. That at least would be amusing. Worst AI ever.

Duke Nukem forever I will be avoiding, eduke32 provides me with my Nukem fix. :)