Disclaimer: The idea for this isn't mine. Another guy did a great version of it over at http://www.fudgie.org/ The only improvement mine has is that it's in flash so it's web-accessible by multiple people at once. His looks cooler, has more data, and probably performs better.

Here's a quick little mini-project I banged out last night.
http://www.agileagenda.com/logview/LogViewAs.html
It shows traffic to my websites as balls flying through space. It uses Red5 on the server to watch the log files, and Flash on the client to display and animate that data. It's watching the websites:

www.agileagenda.com
www.flashyourspace.com
www.marc-hughes.com
www.rogue-development.com

Just open up the flash page, and if nothing is currently happening browse to those sites.

I'll post server & client side post under an MIT license when I get it to a more polished state.