IUMA was set up in 1993 by three university students as a forum for unsigned artists to post and share their music. Emusic
bought the site in 1998 but, as the dotcom bubble burst, they laid off staff members and in 2006 they shut down IUMA completely. Now much of the site's catalog has been rescued and uploaded to the Internet Archive - 680,000 tracks by 25,000 bands and artists! It's available for free streaming or download from http://archive.org/details/iuma-archive
and IMHO it's well worth a browse.
You can read more about IUMA at Wikipedia: https://en.wikipedia.org/wiki/Intern..._Music_Archive