I am highly allergic to cats and dogs. So each of my two sisters had a cat while I was growing up and my mom had a dog. Here are two of my favorites things I did to pay them back.
1. I would put mayonnaise on my dogs snout in a location that he could never quite reach. I licked and licked but could never get it. I think it was probably the happiest moment in his life. My mother on the other hand would totally disagree. When ever we had mayonnaise on the table she would say, "you better not put mayonnaise on the dogs noise." I always did, because it was so damn funny.
2. My sister rescued an emaciated kitty, which become the fattest, laziest cat. I never saw it move at a higher pace than a mosey until one of the funniest days in my life. That day I received a helium filled balloon probably to recognize a very significant achievement in my life. I don't remember the achievement that resulted in that helium filled balloon but I do remember tying the string around my sister's fat cat. It terrified him so much he took of running. He was obviously not used to running because he slammed into the wall, meowed, then backed up and ran into the wall again. It continued for awhile; wall, meow, wall, meow, wall, meow, wall, meow, then for some reason my sister stopped the fun. I probably should have received a helium filled cat balloon for that achievement. Meow.