After auditioning about 15 different headphones I bought Bose Quiet Comfort 15
http://www.bose.ca/controller?DTCLin...VENT&src=k1638
Just amazing. They aren't too big, have a mic for Skype, and sound just freakin' amazing. They also have active noise cancelation (built-in stereo microphones take outside noise and invert it to cancel it out).
To test them out yourself, check out an Apple store. Futureshop and Best buy probably have them too but at Apple they have them connected to ipods, and they let you plug in your own too for a proper listen.