Great and cheap idea!
My husband I own a small business making machines for the greenhouse industry. The control panel of the machine is a sheet of hard plastic 1/4" thick. We changed machine sizes a few years ago and we have a stack of about a dozen or so panels that we can't use. When I made two diaper bags I used HIS "stash" and had him cut them and round corners for me for the bag bottoms. Turned out great!