Artist Ya Ya Chou works in several materials, the most interesting being gummi bears. The Mommy, The Candelabras, and sculptures are nice, but the Bear Rug is not to be missed. The best piece is the Chandelier, which apparently is perfectly fine after two years.
Apparently, Chicago sponsors an annual event where artists make fiberglass cows, and they're displayed throughout the city. See the official Cows on Parade if you don't believe me.