Screenfly - mimics devices for website testing
quirktools.com
quirktools.com
(edit) On a more general note, emulating behavior of a browser/OS combo is not a very good idea as it is trivial to miss quirks that need emulating. It should really be taking an actual browser screenshot on selected device, but then it would've not been different from a ton of similar services... which arguably sprung up because they are doing things rifht and therefore are useful.
Edit: 'no mobile support' = 'doesn't emulate mobile browsers'
I suppose this is useful for testing basic layout without mucking with your UserAgent, though.