Tom Hardy and Michael Fassbender first and foremost. Both practically household names at this point, but consistently put out varying and offbeat work. If Fassbender hasn't won you over yet, check out Frank, in which he'll blow whatever preconceptions you may have about him out of the water. His performance in it is simply incredible, and 99% of the film you don't even see his face! The film being funny in a way reminiscient of the Coen brothers doesn't hurt either.
Hardy has Locke, wherein he alone must carry an entire film doing nothing but sitting in a car alone and talking on a phone, and he pulls it off with flying colours. I haven't seen Legend, where he plays a dual role as identical twins yet, but I've heard good things about his performance in it.
James Macavoy as well, though from me this comes mostly from Filth. His performance in it simply rocks.