Originally Posted by Pooch
Wow ... I thought I'd come to know Chicago pretty well over the past few years - have my eyes been opened! I love to walk, I'm a librarian (no bun, no twinset

) and it's time I saw a game of baseball - interspersing the architecture! So thank you all for each suggestion - I guess I won't be going for a discount carrier to fly elsewhere - I now have a pretty full schedule - and looking forward to it all (especially the cafes/restaurants etc

) Again, many thanks for the great ideas! I hope I can return the favour/s one day ...
A few follow up thoughts:
1) I'm a huge fan of the Chicago Architecture Foundation boat tours as I think were mentioned. If you're a walker, though, they also have dossent led walking tours of downtown. I haven't been on one, but my understanding is that they're tremendous and much more comprehensive than my beloved boat rides.
2) Uno's (29 E Ontario - this location, and this location ONLY) or Due's (619 N Wabash) for the pizza. Other suggestions are servicable, but inadequate. With all due respect to my fellow FTers, don't listen to them.
3) You can go to a Sox game if you want, but doing so to the exclusion of a Cubs game (and by definition, a visit to Wrigley Field) is an unforgivable transgression.
As always ElmhurstNick has produced some of the most interesting suggestions. You might also consider a trip to one of the visitors' galleries at either the Chicago Board of Trade of Chicago Mercantile Exchange if either of them are open at that time. The two are merging and they plan to consolidate floor trading at the CBOT. There's a good chance that down the line, however, they may close floor operations altogether. If you've never seen this kind of thing, it's worth doing so before it's all gone.
Have a great time!!