I didn't want to wait until Friday to post this since it's going fast. Corner Bakery is offering a chance at a free Bacon, Tomato, Mac & 3 cheese but you have to select a date and time. The earliest date I've seen is this Friday (Oct. 19) and the latest is next Thursday (Oct. 25) Corner Bakery RSVP You'll get an email that you will need to print out and bring with you on the time and date you choose. For Chicago locations, you'll have better luck if you don't mind eating a late lunch (or maybe it's a snack) or you're downtown in the evening. Not sure about suburban locations.
Update: I actually really enjoyed this! It's a welcome (albeit higher calorie) addition to the Corner Bakery menu. Just the right amount of bacon and tomato.