so I just walked out of an AT&T store with a brand new 3G iPhone. the kicker is that they did not make me activate in store. my questions are: 1) Is this phone useless unless activated on my plan? 2) If I go in to another store and try to order one (it's for my brother), are they going to recognize that I ordered one last week and not sell me another? 3) Should I sell it on ebay? I just looked and they are going for a ton unopened. additional info: I didn't sign a 2 year contract. I just picked it up and walked out. They didn't even look up my plan in the system.