see p2pweb.net (Score 3, Interesting)

I'm working on a similar project : it's called p2pweb.net.

The site is distributed on 4 web servers : 3 on ADSL lines, one on SourceForge. I use 3 independant DNS to announce the web site. On each DNS I also run NAGIOS to monitor each web site. When one of the web site goes down (or up) a special handler (in perl) is called by NAGIOS and dynamicaly update the DNS entry

see global Load balancing for more details and code examples (in french only, but I am working on an English translation).

I set up the DNS TTL to 300 seconds, and NAGIOS can detect a state change in 2 or 3 minutes. So I can have global fail over in less than 10mn.

I have the system running for some month, and it works very well.

It's a king of "poor man's" akamai.