This would be pretty cool. Shoving a bunch of those tiny exercise trampolines together is effective, sure, but it looks tacky as all hell. Maybe the bigger version can have a net around it?
http://i5.walmartimages.com/dfw/dce07b8c-3c69/k2-_49692a60-b7f7-4be5-b371-28e2af72b133.v8.jpg
Also, if you have any more item suggestions, I recommend putting them here next time 