I started tinkering a tearing things apart to fix them when I was young. I've just always enjoyed the satisfaction of being able to.

Elmers wood glue is awesome on wood and any carpenter know's it but I've also learned that it works great with Porcelain and other small trinkets and what knots that folks accidentally knock over and want to save.

Locktite makes a super glue gel that I used everyday in the Laptop repair business on plastic housings that where to expensive to replace. I would always tell the owner what it would cost to replace or try to repair and warranty the work and never had one returned.

Gorilla Tape is great stuff. My wife and I repaired an old pop up camper that had deteriorating canvas seems with that and by adding 3m spray adhesive. It worked great and we used the camper for a couple years and sold it for profit after being open and honest with the buyer about the repairs.

Ya'll chime in with your ideas for things that you have had success with and please don't derail this thread. I will move it to the useful information sub after folks see it here and contribute.