Question Author
Don't want to give money, but you've given me another good idea - vouchers.
Ratter, LOL :D
Flobadob, WOW! Those eco-spheres are amazing. Now I want one... for myself! :)
Flump, iTunes voucher is a great idea too!
Trigger, I am definitely going to go with one of yours. Encouraging him to get outside is a great idea, as he would spend all day on his games consoles if he could. I'm surprised the boy hasn't got rickets!
Thanks all. Some really good ideas there :-)