A canoe trailer is a great invention - carrying a heavy caonoe for 200 meters isn't fun.

With a trailer, you can also stack most of your luggage in the canoe, so you don't have to do multiple trips for loading and unloading. The trailer can (usually) be packed reasonably flat and just come along on the trip without much trouble.

I'm interested in a DYI canoe trailer project myself. I'm targeting bigger wheels than shown here, though - big wheels run much easier over roots and rocks.

My goal is to be able to hitch my canoe+trailer it to my bike. No, I'm not kidding: There are lots of really nice waterways where the obvious canoe landing sites has a very nice dirt road all the way down to the water - but that road is blocked for cars. Being able to park at the gate and wheel or bike all my gear plus canoe from there down to the water vastly expands my options.