I don't really like to buy the store made costumes so I try to improvise as much as I can. My son's first Halloween I made him a Blue costume by taking a blue one piece pajama and sticking little blue felt spots all around. I also cut off the fingers of a pair of old blue gloves and pinned one to the butt for Blue's tail and then fastened blue felt ears to a headband. The next year he was Buzz Lightyear. Since I couldn't find a white sweat shirt in his size, I took one of mine and cut the arms and the waist part to fit his body. Then I took some felt pieces and sewed them to the shirt for the "Space Ranger" buttons and such. For the rockets, I fastened some glowing chem lights to also keep him safe too. He wore that costume well after Halloween.
This year Dominik has decided to be a dinosaur. His sister is going to be a baby dinosaur with her legs, arms and tail poking out of the egg shell and, if I can manage to get started early enough, I am going to be cave woman mom. It should be cute.