I've developed a bad habit.
When I'm in meetings I don't want to be in (which is to say, at least half an hour every day) I've taken to scrolling through ebay listings for vintage toys and collectibles and computers.
So far I've been good. I haven't spent very much money. (Around $50, and on things that I had already explicitly planned to purchase, but at better prices than I had expected to pay) but the temptation grows day by day.