I went into T-Mobile here in Austin to get a new SIM card. The guy had never seen an N900, and (thankfully) handed it to me to pull the back off, but he was not a total ***** like some of you seem to have run into. Actually, I was the one who had a moment of confusion wondering why the sim card slot was empty when he pointed out I was looking in the SD card slot (I really don't open the back that often!).