The 2008 STC World Championship, a free, 9-round event with a 60+30 time control, starts July 14th on the Free Internet Chess Server, Internet Chess Club, and World Chess Live.
The top 16 finishers will advance the STC WC Finals; a knockout tournament, starting September 15th. Full details here. I qualified for the last finals, back in 2005, by winning the now-defunct U.S. Chess Live section.
The entry deadline is Sunday, July 13th at 5:00 p.m. EDT (21:00 GMT). However, late joins will be accepted until round 3.
To play, become an ICC, FICS or WCL member, join the STC Bunch, login and register for the tournament.