Comment FreePBX and Mediatomb (Score 1) 620
I love old laptops!
I've got a couple of PIII's with busted displays.
One is running Centos 5.1 with Asterisk + Freepbx, and does a fine job and running the VoIP setup in my house.
The second runs Ubuntu server with TorrentFlux + MediaTomb. A perfect setup for downloading torrents via a web interface, and serving up media to my PS3 via UPnP.