You're not going to find anything truly similar to B&Ws unless you up your budget by a lot (double).
In your price range though, the best you're going to find is probably Beyerdynamic DT880s or Denon D2000s (D2000 bass is fairly uncontrolled, I'd probably recommend the DT880s unless you want to up your budget and get D5000s).
Now if you wanted something completely different from B&W, K701/2 like the first guy recommended is essentially the complete opposite. Rather than musical, they are very analytical. If you're the kind of person who enjoys sitting there listening for all the details and flaws of the music, rather than just enjoying it, then get K701s.
Personally I couldn't stand the K701s, couldn't even get my foot tapping. On the other hand, some of my friends absolutely adore them.