A few different programs here

[napho]

I've mentioned Andromeda before. It streams music, some contributed by the artists.

http://www.turnstyle.com/andromeda/

Netmess appears to be in it's infancy...maybe something to look for in the future.

http://sourceforge.net/projects/nmclient/

This Plebio thing is supposed to be a search engine for stuff on your hard drive. Sounds lame to me.

http://plebio.com/