I think a spectacular toy box creation would be to make a Calvinball arena.
Calvinball is a game created by the title characters within the comic strip Calvin & Hobbes.
The first rule of Calvinball is that you must never play the game the same way twice.
Most everything else, you can make up as you go.
http://calvinandhobbes.wikia.com/wiki/Calvinball
http://www.bartel.org/calvinball/
What do you guys think?