What are your top 10 favorite single-player first-person shooters?

[CollectiveCynic]

Machina said:

Severance said:

are portal and Mirrors Edge really FPSes?  i find them more of a Platformer (Mirror's Edge) and a Puzzler (Portal)

i don't they're "Shooters" ya know?

You're always in first person, and almost always have a gun... which you shoot with, constantly. There, that's my justification :p

It's not combat focused as real first-person shooters.