Not sure if this was suggested before...
http://en.wikipedia.org/wiki/Matryoshka_doll
but how about a collection of Matryoshka Dolls based on the 11 giants? So you would have these 11 dolls that each go inside one another based off each of the 11 giants. They would all be of different sizes.
Then you could get a special bonus or feature when all 11 giant dolls are stacked together as one.
I played Stacking by Double Fine recently, but I've always thought Matryoshka dolls were pretty interesting.