The AIM protocol will open an AOL Instant Messenger IM window with the attributes specified in the link. links begin with aim:goim?.
Examples of modifiers:
- screenname=
- aim:goim?screenname=notarealuseratall
- mesage=
- aim:goim?message=nothing+at+all+here
Ironically, Wikipedia only supports common protocols, so those adresses must be copied and pasted into a browser to work.
All information derived from looking at the "AIM" link formation at Gizmodo