I listen to a bit of everything. I do have a variety of headphones, mainly resulting from collectoritis or upgradeitis.
For home use, I could be pretty happy if I could only have my Sennheisers, preferably the HD580s, but I could live with just the HD497s too (the 580s are more comfortable and sound ultimately better - the 497s are lighter weight and more easily driven, with an engaging, detailed sound). The 497s pair well with all my gear, although I'd have to say they are most magical when driven out of my portable MD recorder (Sony MZ-N505). I use the 580s out of the jack on my Yamaha receiver (I know, sacrilege, but it has a pretty decent DAC) and they sound very good. I'm sure I'll get around to finding an amp eventually.
For portable use... the HD497s are too large and weird-looking for me to wear them outside. I like my Sportapros in this capacity. They need a bit of power considering they are cheap portable headphones, and the midbass is as overblown as everyone says it is, but they are nevertheless very comfortable and suitable for all kinds of music. The Sennheiser MX500s sound decent, for ear buds, but I find them uncomfortable to wear after a while and they fall out somewhat easily from my ears. They also match well with the portable MD.
You know, for all the abuse Sony MD recorders suffer at the hands of Sharp fans, I think they still sound quite good, and even with some fraction of the current of Sharp headphone outputs, there is still enough current to drive most 32 ohm headphones to reasonable levels.