I'm looking for a nice set of cans.

Don't be turned off that these say DJ headphones. They have good SQ and are way under $300. No active noise cancellation though but they do a good job of isolating ambient noise.

AIAIAI TMA-1 DJ Headphones

http://www.aiaiai.dk/store/headphones/tma-1

Definitely easy to carry and can be used with portable devices.

Another favorite of mine but isn't so travel friendly IMO due to the rather long coiled cord it employs is the Sony MDR V6. Be sure to get the velour pads as an upgrade. Definitely improves the comfort.

Roscoeiii thanks for the response! That's what i figured about open cans but i wanted to ask first. the Grados are tempting but since they are all open they won't work.

as far as my preferences go i'm very eclectic. rock, classical, musicals, electronic/techno. Honestly as long as it sounds good i'll listen to it. As far as the "type" of sound I'd say a combination of sound stage and accuracy is closest to what i like, i don't want artificial bass humps like the Beats have. and i appreciate treble but i like a more even balance of bass, mid, and treble. I don't have a dedicated head phone amp yet, but i'd like to get one eventually. Id really love to have one for my portable use but power supply is a problem. What portable headphone amp sounds good and has a 6hour+ battery life and is worth the money?

I also recommend headroom dot com for good evaluations of all kinds of headphones and they are friendly and easy to talk to on the phone. I have bought many from them and have always been pleased. 30 day return policy. You will have to decided on many things but if you are going to use them in noisy environments you may consider in-ear monitors. Good luck.

Thanks Tgrisham i'll check out headroom. I've tried in-ear monitors but there is something about the shape of my ear, they never stay in for the length of a song. thy just slide right out. I've tried many different types and shapes but nothing will stay in.

I've found that electronic noise-cancelling cans can be bothersome after a while (perhaps I'm just sensitive to them - they give me the sensation of "sucking on my ears" when they are turned out...). But I've also found that decent in-ear monitors can do a very good job of blocking outside noise. The key is getting a good seal in your ear. Full sized cans will generally sound better of course, but at the cost of additional bulk and less effective noise cancellation (and audibility to your neighbors for open designs).

Pairing a decent set of IEMs with a nice portable amp can be very satisfying, and not necessarily too $$$. Feed it lossless files from a portable device and you're good to go.

I use a Ray Samuels portable amp at work, and bring it with me on planes/trains too, and really like it (its an SR71A). I use it with IEMs (one of the upper-line Shures - can't remember model name - along with UltimateEars TripleFi 10s) plus my full sizers (Beyer T1 and Audez'e LCD2) and it does a great job. It's a great sidekick to a full-blown headphone amp, or a substitute for one in a pinch.