Some suggestions I put forth in an August 12, 2001 thread on FlyerTalk merchandise ideas:
<font face="Verdana, Arial, Helvetica, sans-serif" size="2">Tee-Shirt Ideas:
"I Was A Teenage Airline Mileage Whore!"
"I'm A Frequent Flyer. Marry Me And Fly Free!"
"Hello There, Darlin'. What's Your Fare Code?"
"Can You Say 'Voluntary Denied Boarding Compensation?'"
"I'll Have The Chicken"
"A Hard Landing Is Good To Find"
"Would You Like A Nice Piece Of Swiss Chocolate, Little Gate Agent?"
... and ...
"I'm With Stimpy" (to be worn only on visits to Staples Center)</font>