Do any of you you know Audiogalaxy? Free online service, download an app to your computer and one to your iPhone, and then you can listen to any music on your computer wherever your iPhone has an Internet connection, or in the browser on any computer anywhere. Freakily easy. (The music files need to be tagged, of course, which many of mine aren't, but it handles ogg/vorbis and flac as well as mp3 and aac.)
I'm quite impressed, actually - now I have a reason to get all my files properly tagged.