PS3 Media Server is a java app that streams media to your PS3.
It is reported to run under Windows or Linux. You have to have a recent java install to run it.
I untarred it under Linux. There's no installation. You just run the PMS.sh script and under Fedora Core 13 it just fired up.
On the PS3 you have to enable Settings -> Network Settings -> Media Server Connection.
If you have multiple network devices you may have to explicitly set one from the configuration screen and restart the app.
The only problem I ran into is the stock iptables rules on Fedora Core 13 prevented the media server and PS3 from seeing each other. Turning off iptables worked around the problem. I haven't explored which ports it uses.
You can configure what folders it exports.
So I was viewing videos and photos from my workstations on my big screen tv. The quality of the video that my little Cybershot HX5V takes is nothing short of incredible. I regret not shooting vastly more video.