Well, there's this: http://aacplugin.sourceforge.net/

I'm not sure what kind of changes apple may have made to the aac format. I'm going to test it out when I get home tonight. If I can't easily move the AAC files to my linux box (which stores all my mp3s) and at least sync them to the empeg (native or converted) I won't use the service much.

Cool idea though.