The Sony MDR-V6 / MDR-7506 gets a lot of love around here, even from folks who generally dislike Sony on principle.
I have the Grado SR-60 and the Sennheiser HD-280Pro. Both models are well regarded in this price range (as are the Grado SR-80s). The Grados are an open design, so they let most noise in and leak noise out to some degree. The Sennheiser are a sealed design, and block out noise - a lot.
The Grados generally sound better to me (although the Senns do have more bass extension), but the noise-blocking of the Senns is very nice.
The other recommendations are all promising, too.