I don't know how you might do it but I keep thinking there should be some way to do a tie-in with the Oscar Meyer Weinermobile .
I'm also guessing that you can't have more than one Slinky Dog due to the weight requirement and relative lack of "pulling" ability/demand placed on the spring -- that is, slinking, weight car, slinky, weight car, etc. A string of these "hot dogs" would be hilarious.
TRRR