OIC. Glad there's a top.
My dwarves can still jump that high though--they're netherland dwarves and have no problem jumping up on to the futon which is at least 2 ft from the floor.
I thought of some toy ideas. A good cheap toy is a toilet paper tube filled with hay--they chew, eat, and throw it. Wood toys are good to chew on--any safe wood is good--avoid treated wood or pine/cedar. Keys made for babies to play with are a big hit for throwing. Balls, baskets, and wreaths made of untreated wicker are great too. A hidey box for when he's out playing can be lots of fun. Some bunnies like to dig on old phone books too.