Meh... unlimited plans are overrated.. I have one.. and since I have my 3gs September 2009 I have used: *checks iPhone* 3.1 gb... thats like 300 mb a month...
and for people who want to use thethering on the iPhone: http://www.benm.at/2009/06/13/helpbenmat/
Face the future.. Gamecenter ID: nikkom_nl (oh no he didn't!!)