i've been doing a good bit of research here as well ... for basically the same situation. Using a set of cans out of a Computer as well as an MP3 player. I am a college student, which also adds that i need isolation/closed cans. Maybe you need the same.
I searched the AKG K 26 P's and didn't find that they were that exciting. Many were let down by them, but take that for what its worth. Many head-fi'ers here have superb taste and sensitive ears - much more sensitive than mine. So, basically, for me, i decided that they'd sound much better to me than other cans, but that there ARE better alternatives to them, and possibly even for cheaper. i can't figure out though, why Headroom gave them such high marks ... when here, they never got that warm of a reception.
You many want to look for a nice set of Canal Phones, as well. Er6i's were recommended to me, and possibly some out of the Shure line (e2c, e3c, etc.)
for cheap, i'm pretty sure you won't be let down by a pair of Koss KSC-75's and many people like the HD201's. at about $20 shipped, i'm gonna give them a try.