UShare
From Amahi Wiki
Ushare is a great app for streaming to the Xbox 360 (well tested, with avi files), PS3 (not so well tested) and perhaps other UPnP clients.
Ushare has an issue: it does not refresh it's database periodically with new files being added.
So, any time you add any files to your movies/music/pictures folders, please restart it via the servers area (under Setup -> Applications -> Servers, with advanced settings turned on), or by hand as root, with
service amahi-ushare restart
We are considering issuing the research via a crontab every few minutes.