First Time in Chicago: Suggestions?

[mooby]

I've got an old neighbor into model trains, and I remember one time he recommended checking out the Museum of Science and Industry in Chicago, supposedly they have a really huge exhibit there along with some other neat exhibits. I can't say I know much about it but I put it on ice in case I ever find myself in Chicago with nothing to do lol. I like the ideas so far though, I'd probably visit Wrigley Field just for the experience and the zoo is always neat. Having never had an authentic Chi-style pizza that would be on my list too.