[hand waving to the riff raff...]
beepster - the HD280's aren't bad and I can wear them longer than most, but they still hurt my head after a while. the most comfortable ones I've ever worn are the HD515's but they're not for critical listening - they're for pleasure listening only.
of course, pleasure listening is what I'm doing at work and that would help, but I also don't want to leave expensive headphones laying around at work either.
Mike - no, I don't watch a lot of TV, but that might be good with bigger cushions.
the cushions on the HD515's are fabric and that's one thing that helps, I believe, because they're not "plastic" or "imitation leathery type stuff that wraps the cushion. pliable as they are, they're still not as pliable as woven fabric.
of course, the HD515's even if they were made for critical listening, tend to break easily on me. I have gone thru 2 pair and have not replaced the last ones. they tend to break at the plastic part where the head gear meets the ear piece.