I agree with Sidssp, the 580 and 600 are very comfortable. For me they were the most confortable and best sounding of any traditional headphone I tried. Problem was I needed isolation (580 and 600 are open-air type) so I went with the Etymotic ER-4P. You might consider the Etymotic if you have problems with traditional headphones, but be forewarned they can't really be used while you are moving due to microphonics and some people do not like anything stuck in their ear!
Headphone I can stand for more than 1 hour
Every headphone I have ever had starts to drive me crazy after 1 hour. I started with the Sennheiser HD 414. Warm foam cushions and push too much on my ears. Tried the AKG K-1000. Too heavy and push on the side of my head. Grado SR 325 - too warm. Why can't anyone make a headphone that sounds good and one I can use for a couple of hours? Have you found a comfortable one yet?