As noted over at walking paper AIM now has official status and as noted in a comment you don’t have to sign up to use it (unofficially) though that may break in the future.
Right now all you have to do is change the URL below to have your screen name at the end (case sensitive so watch out). Put this as the src in a image tag. If you enter the URL in a browser it should redirect to the graphic of your status if you want to test. api.oscar.aol.com/SOA/key=P… We’ll see how long this lasts. The URL leads me to believe until Jan 2006. Hopefully the other services get an official presence system going to as I dislike the whole 3rd-party hack thing.
View source if you need my screenname for some reason. I can’t guareentee I’ll respond to “non-buddies”.