CuCN and the admins have the ability to mess around with thier profile's CSS script, which does that.
CuCN once made his page an epileptic mess of lines. If you think UTA's anomaly was an error... Oh boy.
Edit frenzy:
LINK ALL OF THE EDITED PROFILE PAGES
DIVULGE ALL THE SECRETS
Willng3 is a bootiful example.
SpikeSpiegel is a classy example.
Dawn to Dusk is a heroic example.
Deuce22 is a kinky example.
Skotadi Phobos is an effervescent example.
Tiko is an informative example; it seems anyone with an ultimate profile can scribble this stuff on thier media. However, only special people can make it play on the background and mess thier stuff up.