Looking for FPS (PC) with features like Army of Two (PS3)

First topic as user - yay :)

Anyways:
A buddy and my self bought a PS3 a while ago, and just yesterday we invested in a completely nice game; Army of Two - omg the brilliance! Fantastic graphics (even without HD - I can't begin to imagine the HD!), and terrific weapon options imo. I just recently got a computer at my disposal, so now I'm also started to get interested in some of the cool PC games thats out there.

The thing I like about Army of Two is the way you can upgrade your weapons. For those who haven't tried/seen Army of Two the following options are: Barrel, Silencer, Clip, Shield (if possible), attachments and a cpl of more (haven't tried it that much, just yet :p).

So the real question is;
Does anyone know any PC games with similar weapon options and/or options for gear (like helmets, armor or so)?

Also I might add, that I'm also familiar to gameplays like Splinter Cell Double Agent (Again PS3 - haven't tried PC versions), wich also offers a unique gameplay imo - It's cool to switch gameplays once in a while, so you don't get bored with gunning people down easily.

Also I should add some computer specs (in order to meet system reqs - I'm not looking for comments/help on hardware :))
Athlon 3.8+, 2GB DDR II and a GeForce 7950GT

Cheers :) Hope the forum is as nice as the rest of this fabulous site :D

you can have a look at the following games off the top of my head.im guessing youre looking for shooters with changing gameaply and maybe some co-op:

Crysis

Rainbow Six Vegas 1+2

Ghost Recon Advanced Warfighter 1+2

Gears of War

Deus Ex

Deus Ex Invisible War

Stalker

Call of Juarez

Bioshock

I'm also looking for a game that offers some shopping for both gear and weapon upgrades.
I was thinking about looking at crysis, after reading the reviews. The enviroment sounds tempting :)

but does any of the games you mention offer a shopping section, for my gucci fetish? hehe

I'll have a look into Bioshock at least :) I've seen S.T.A.L.K.E.R and weren't that impressed by the graphics I have to admit :(

Mapple; May seem so, I'm affraid.. I'll just hang on for a while, on the PC scene, and see what comes up hence I love playing WASD and mouse games ^^

Well :) Thanks for the cool and very fast comments ^^

you can have a look at the following games off the top of my head.im guessing youre looking for shooters with changing gameaply and maybe some co-op:

Crysis

Rainbow Six Vegas 1+2

Ghost Recon Advanced Warfighter 1+2

Gears of War

Deus Ex

Deus Ex Invisible War

Stalker

Call of Juarez

Bioshock

crazyfist36

i love all this games too man