Well, there was that news story last week about a kid in California who took a basically worthless cell phone and kept trading (via CraigsList) up and up and up until he ended up with a Porsche. I know that can be done because before the Web I used a local L.A. paper that specialized in just classifieds (can't remember the name but post if you know) back in the 80s to buy a Sony tape recorder for $5 which I traded for a portable ball Olivetti typewriter which I then traded for a round trip ticket from L.A. to Ft. Lauderdale.
Someday couponing might get you a time share on the moon.