I must admit I am in love with this design which doesn't originally belong to me. In my opinion, it has it all: use of recycled items, fun, functional, unique, would put a smile on any kid (or adult) any time!
I have not tried it myself yet but it doesn't seem to be an extremely challenging project to work on. I am definitely looking forward to coming up with my own design (or Mr. Junior may like to design it by himself).
Enjoy something that makes you smile today!