In the future, if most products contain RFID tags, it will be possible (with the right "reader") to know what discarded items are in a dumpster from a distance, without having to look inside. It will be possible to do a variation on wardriving where you search for physical objects instead of wi-fi access. With the right software, you could even create a "wish list" of the objects you want and get notified if they are nearby.
I need a pair of headphones, notify me know when one is nearby. [Bleep!] Hey, look, someone must have thrown away a pair of headphones in that garbage can over there! Score!
I need to borrow a bottle opener . . . [bleep!] . . . signal coming from over there . . . "Excuse me, sir . . ."
But there are weirder uses for this. Burglars could find out what is in your house without going inside. Passers-by could find out what brand of underwear you're wearing. People driving by your house could learn which books are on your shelf. It will be a strange world.