1.Vaas Montenegro from Far Cry 3
Michael Mando did very very great on the voice of Vass.He just made this game great.

2.Handsome Jack From Borderlands 2
His audio logs were the best thing in Borderlands 2 and it kept me right in the story.

3.Adam Jensen From Deus Ex.
Elias Toufexis nailed it on the voice of Adam Jensen.I think his voice is one of the coolest voice in video games.

I know he does the shows and movies but doesn't Mark Hamill also have some work as the Joker in a few games?

Oh, it's this thread again ;-)

I'll give my usual response: Tim Curry as Stratos in Sacrifice.

Dominic Armato as Guybrush Threepwood. Normally, when a character I'm already familar with is voice-acted for the first tiem, it takes a while for the voice to feel right (if it ever does). The moment he starts speaking at the start of Curse, however, my immediate thought was "Yup, that's exactly how Guybrush Threepwood should sound".

Gabriel Angelos and his perfect voice for 40K

Most of GTA >= 3's voice acting has been pretty excellent. Of course they took on some heavy duty hollywood actors:
https://www.youtube.com/watch?v=lhJ7vPPYq_M

And can't forget about this perfect immortal machine. She/it still sends chills down my spine when I play the game.

Jennifer Hale, obviously.

Robert Belgrade, who voiced Alucard in Castlevania: Symphony of the Night.

Jean luc Picard in oblivion (yes I know it's Patrick Stewart)

Whoever does calebs voice in blood

Tony Jay. Did voices in Legacy of Kain series (the elder god was great) among many other voices in video games and movies.

Whoever does the voices in HuniePop. :P

Well no doubt, everyone involved in Dead Space 2 and Demon Souls, the voice acting it's this 2 games it's simply amazing, honestly in like 15+ years of gaming I've never played anything close in terms of voice acting.

Not sure if the best, but Jaheira in Baldur's Gate always cracked me up with her sarcastic:

"Yes, oh omnipresent authority figure?"

https://www.youtube.com/watch?v=KpHTG6XlYOA#t=24

Google says it is played by Heidi Shannon.

http://www.imdb.com/name/nm0788289/?ref_=nv_sr_1

The narrator in Bastion

I wouldn’t call it voice acting because he just speaks like he speaks normally ;)

Watch/listen to this [url=Adam Jensen plays Deus Ex video]https://www.youtube.com/watch?v=flszuT3ROdo[/url]
It’s a funny video.

I love John St. John’s Duke Nukem stuff. His normal voice sounds very different from the Duke.

Ulysses in "Fallout: New Vegas"; listen to his long historical account of events, which triggers at the end of the Lonesome Road DLC -- you won't hear better voice acting than that.