Looking for a FPS with a good single player campaign. Suggestions?

[LordMatrix]

pots555 said:

I love single player campaigns.  I usually play RPG's but I happened to stumble upon Crysis 2.
Wow!  This game as completly changed my view of first person shooters.  And now, I want more, but I am only interested in good and engaging single player campaigns.  Length is not that important to me, as long as the quality of the experience is high and the story engaging.  For the record, I thought Crysis 2 single player experience was truly awesome. 

So, do you have any suggestions?  I have just acquired Call of Duty 4 : Modern Warfare.  Anything else?
I hear Half-life is pretty good.

Thanks!

If you looking for a shooter with good story here are some that come to mind....

Bioshock, Half-Life 2, Bulletstorm, The Chronicles of Riddick, Halo Reach, Resistance: Fall of Man.

Those are a handful of the more interesting ones.