Or you could just buy a Pelican box with see-through lid. Their smaller boxes have this lid, and they hold keys, film canisters, and other small items. I use the smallest one, the 1010, but they make several sizes with the see-through lid. Someone I know keeps his Nikon Coolpix camera inside the 1010.

The Pelican boxes are waterproof and have purge valves. Yes, I have tested mine in water, as well as two of the large boxes meant to hold SLR cameras and lenses.

Peanut butter jar is a good idea for some items but I would not trust it to hold any electronics (car alarm system remotes, phones, cameras). If you drop it it is more likely to crack than the Pelican boxes.

You can buy Pelican boxes via mail order/Internet shopping for *much* less than a local retail store's prices. Same thing for high-quality dry bags--another option for dry storage.

I have stored things in a Rubbermaid sandwich bin (like Tupperware) but frankly do not trust it for immersion. Ditto Zip-lok bags and the ilk.