There are some really good headphones for under 100 at audiocubes.com.
They come straight from japan and you can't get them anywhere here.
they rock they have great dynamic range 5-25,000hrz
They alos fold up, they are sony eggos MDR-66's
THe best are the MDR-77's but to bad they stopped making these a couple of years ago.
I will stand behind these headphones as being comfortable which I can't say for alot of models out there.
If you can find a better sounding pair for under a 150.00 let me know cause I have spent alot of time searching.
Most people don't know about these headphones. I found them when I was living in japan so that's the only reason I know about them.
Good luck and if you have any questions let me know and i will be happy to help.