Supposedly the first of its kind, the Aiwa UZ-PS128 is not only a pair of fairly decent looking headphones, but also an MP3 player and an audio recorder. The analog input lets you record from any audio source onto the unit's 128MB of flash. Alternatively, you can simply transfer files from your PC to the headphones with a USB cable.
The Aiwa headphones support a variety of digital audio formats other than MP3, including WMA and AAC, which is good news for people using iTunes to rip their music. You can find it online for anywhere from about $50 to more than $165, so it's advisable to shop around.