Today I was getting some canning jars ready to be filled with tomatoes. One thing you must do with your old jars is run a finger over the rim of the opening to make sure there are no nicks, because if there's the slightest flaw on that rim, the jar of tomatoes won't seal. I throw away such jars, but my mother didn't.
Oh no, if there was any possible use for an object, Mother wouldn't think of tossing it. She had a collection of old-time zinc lids; with these, you buy some rubber rings and then screw on the lid. The jar seals at the lower rim, instead of at the mouth.
So I went to Google to see if those rubber rings can be found. Indeed, Lehman's has them. I assume you'd have to look on Ebay to find the old-style zinc lids, though.
Just another random memory sparked by my canning adventures.