What to make out of 4 bowling pins?

Flip them over - the round parts can be the bottom and the table top is attached to the flat side.

Mount them to a board at an upwards angle and maybe you can hang jackets on them?

Now I want to go get my own bowling pins!!

And a gallon of vegetable oil? Or whatever it is they use to make the bowling lanes slippery?

You can surely fashion a pair of nunchaku out of bowling pins.

And you’d have an acceptable ninja turtle weapon!