GENTLEMEN! have I got a treat especial for you today!
Picture this! You're in the woods going after a geocache, you search and you search and finally you spot the jeezless thing, you open it up and son of a diddly, the thing's full of water and the log book is all turned to schmoo. "Needs Maintenance" as they say in the parlance of the geocachers. There has GOT to be a better way!
So I present to you, the Skookum Cache.
Inside you'll find an aluminum plate, some foam rubber sheet, a thumb detector and a set of the finest, and by finest I mean cheapest Chinesium alphanumeric marking punches that the Canuckistan Amazon had to offer.
The aluminum plate is the log book. Set the aluminum on the cache container with the foam sheet in between, on account of not marking up the back side of the plate when you're marking up the front side of it. Then take the punches and the thumb detector, engage your safety squints and engrave your name into the plate.
Getting wet won't be a problem for this log book. Provided the muggles don't get to it, it should chooch on for years and years.
Keep yer stick in a vice!