Help! I need to think like a tourist!

In Chicago, there is an easy way to spot a tourist.  Just look for the people who are looking up.  Locals walk fast and stare straight ahead, but the tourists are checking out all the tall buildings.  And the locals tend to get very annoyed by the tourists.  Well, in an effort to become a Chicagoan as quickly as possible, I have realized that I never did the tourist thing here.  This puts me at a disadvantage when playing hostess to out-of-towners!  My friend L is coming to visit me this weekend, and in preparation for her visit, I've been racking my brain for "the things one should do when one visits Chicago," and I've come to the conclusion that I don't know what those things are!  Of course I've been shopping on Michigan Ave, so that's a given (plus some shopping in places the locals keep secret because the prices are better).  And I think we'll go to the Field Museum.  But what other attractions or restaurants have you all heard of that are the "typical" or exciting places to go in Chicago?  I need your help!  Don't make me break out the guidebooks! :)