Ajax Online Chat

I am using Bluehost as my web hosting company. I am making an online chat using ajax (XMLHTTPRequest object). I ran into some trouble because I was exceeding the CPU limit. Probably because every half a second or so it checks for new messages. Right now I have many "chat" windows open to test to see if it will do it again. Hopefully not.

For the chat I am using the polling technique, which may not be the best but it works.

It would be cool to learn "Comet." Comet might be a dorky name but I think its good to have something simple to call it.

Exceeded CPU again!