I remember my inflation meter was candy bars at the grocery check-out. When I was a kid, I'd go shopping with my mom, and she'd reward me by letting me buy a bit of candy (3 bars for 99 cents when on sale). It was regularly priced at 54 cents/bar, which was just too expensive. Now a "sale" on the same bar of candy is "Buy 2 Get 1 Free!" at 89 cents a pop.
Candy has just about doubled in price (and "Fun Size" Milky Ways are noticeably smaller). Even kids can understand inflation!