Reactee

Want to send a message?  Why not do it with your own custom t-shirt complete with text response number?  Just go to Reactee.com and choose your slogan and keyword.  When spectators  text your keyword to the number shown they will receive a text message of your specification.  You can change your customized message as often as you want.  Options are available to notify your cell phone whenever your shirt elicits a text, or allow for texters to send you a message back.  And all this fun for only $20-27! (Found through NOTCOT)