I was cruising around on slashdot and I found an article on a TCP/IP stack written entirely in PHP. I found it very interesting because if someone was to really work on this code it could mean that websites could handle more connections at present time the only limiting factor would be bandwith.

http://www.sics.se/~adam/phpstack/

the test server is here:

http://193.10.67.151/index.php

It can only dish out a very small HTML page at this time but I would say if it was worked on more it could be fixed . Thought you guys might find this interesting.