"hey ... you're hot. and you have no clue who this is :)"
Don't freak out.
Also don't think you're special.
It's pranksters who look at blog sites where the blogger lists their AIM ID publically, google for "TheGreatHatsby", "Project Upstream", or see the profile description of themissinghat community for info on similar shenanigans.
--signed: a buzzkill :)