Actually you need to have 3 sitting at $0 and one reporting a balance of less than 9%. So just charge something small on one card and let it report a balance.
July 2013 score: EQ FICO 819, TU08 778, EX "806 lender pull 07/26/2013
Goal Score: All Scores 760+, Newest goal 800+
Take the myFICO Fitness Challenge
Current scores after adding $81K in CLs and 2 new cars since July 2013
EQ:809 TU 777 EX 790 Now it's just garden time!
June 2017 update: All scores over 820, just pure gardening now.