It's in beta, but it allows me to stream my entire collection from my home computer to my phone wherever I have a connection! Quite snappy over 4g too! Found the initial recommendation over at Lifehacker one day
This assumes you leave your home system running which is usually better for it anyways....
I have winamp installed but haven't really used it much yet...
so bewtween audiogalaxy and pandora I'm usually good to go!