I've heard of JB Weld, just never for wood. Probably most of what I will need it for is going to be wood. I do have some places where I need to replace the wood, but there are many places that would definitely benefit from the Bondo. Like Chet mentioned, where the boards butt together do have some gaps that would look a lot better if they were continuous and clean. Thanks guys!
They make a lot of different things.