I'm not a big fan of holiday schmaltz, but the Winter Wonderland exhibit at the Chicago Botanical Gardens is actually worth it. They've built elaborate recreations of Chicago landmarks using twigs, leaves, acorns, nuts, and other natural elements. Unlike art in other venues, there's a visceral reaction: it smells fantastic and is permeated by the sound of running water and model trains. Plus, the greenhouses are open in the new Regenstein Center if you want to feel tropical despite the cold temperatures. There's something neat about looking at cactus when the ground around you is covered in snow.