One of my favorite things to do in Chicago is walk around Downtown. Not going anywhere in particular, you run across some really interesting shops and restaurants, and it's a great scene for people watching.
There are some great hidden corners around the area, tucked between the towering buildings and square blocks.
Downtown in the Loop is Chicago's City Hall and the Cook County administration building, each entity occupying a portion of this single large, grand building. It has a rooftop garden, as well, which is open to the public but only at certain times or by tour. It is a Beaux-Arts building completed in 1911.
My friend helped me start the long walk downtown, showing me places as we made our way around. I live close to Downtown but rarely go there. Once I got him intrested in photography, he took me downtown and we shot photo all around. Now I love going downtown as this also started my interest in going place on my own hopfully in 2007. Some great place to look for are Navy Pier, Sears Tower, John Hancock Center, Millennium Park, Field Museum and more