OMG, stickers! When I was in elementary school circa early 1970s, good automotive stickers were worth their weight in gold on the playground.
I hit paydirt when my grandmother gifted me with a couple of STP stickers one day. The Shell station she took her Plymouth Fury to for fill-ups (full serve only back in those days) had scads of them and gave them out for the asking to their regular customers. Well, I convinced her that she needed to get AS MANY AS POSSIBLE EVERY TIME SHE WENT THERE. I think she drained the guy's supply over her next several visits, and they were like cigarettes in prison to my friends.
By the time the trading dust settled, I had scored an array of great stickers, including the famous Clay Smith Cams woodpecker, Cherry Bomb, Holley, and scads of others. I think they ended up stuck to my bedroom desk or something, and now they're in a landfill somewhere I'm sure.
But, ah, stickers. Just the smell of their (probably) toxic vinyl was nirvana in my youth.