I have a Zune… and an iPhone and spread my computing time between 3 different machines. Occasionally I like to listen to my person music collection that is stored on one computer when I’m using another one. In the past, this has caused some frustration. Okay, quite a bit of frustration.
Enter the Amazon Cloud Player.
It allows me to upload MP3s I’ve already purchased and automatically imports music that I purchase from Amazon (which is my preferred method as I can transfer those files to either my Zune or iPhone).
I can also select the option to automatically download my music purchases onto one or more computers (and different devices).
When I want to play the music I have already downloaded or uploaded from my collection, I can use my preferred browser and launch the Cloud Player.
Consider yourself privileged. My musical choices are rather personal. I don’t show my collection to just anyone.
I’ve also heard some good things about Google Music but I haven’t tested it myself.