Not sure how high this is on the lazy scale, but after a few minutes of winding and flying my son's rubber band powered balsa airplane. I knew there had to be a better way. A quick amazon search dashed my hopes of inventing something new, but I made it anyway in about 3 minutes and for almost nothing.
All you need is a drill bit to socket adapter, 10mm socket(or any size) and of course the plane. Tools required are grinder/saw, drill and metal file.
Hold the socket up to the propeller and mark the width and depth of your cuts. I tried to taper it a little but it didn't see to matter. Cut the slot out on both sides and file the edges smooth. Put your socket on the adapter and into your drill and your ready to go.
Now enjoy the simple fun of a rubber band airplane but be careful with your speed so that you don't over wind the rubber band and break it.