Which British actors have the best American accents?

[fangirl_says]

Buzzsugar is talking about which British actors have the best American accents. Not surprisingly, Hugh Laurie is at the top of their list, and Anna Friel from Pushing Daisies is #2. There are quite a few other fandom favorites, too, including Jamie Bamber, whose teeny tiny towel American accent impresses me on a weekly basis. There's also Lena Headly from Terminator: The Sarah Connor Chronicles, who must be good, because I didn't realize she wasn't American, and the late, lamented Jericho's Lennie James.

Who else has a great American accent?

(Please do ignore the fact that I completely missed the "TV" part of the question and posted a comment about Ewan McGregor. *is goober*)

Edit: Updated with the actual link this time *facepalms*