The mp3 format can handle multiple artists per track (in the form of "artist1\artist2"), and as far as I know other modern music formats can do the same thing. However, Rhythmbox (my default music player) seems to be capable of only reading the first artist. Are there any music players that can read and sort songs with multiple artists, or a plugin for Rhythmbox that can provide this functionality?
Quod Libet will handle multiple values for pretty much any tag where supported by the format (e.g. mp3). It also knows about other person-like tags such as