I wish I had seen this before the weekend, but for others who see this later, you can park free on the north side of Wacker Drive just west of Michigan Avenue all day on Sunday, beginning at midnight on Saturday until midnight on Sunday (this is just a few blocks from the hotel). No meters, no parking boxes. So, if you don't need the car at all that day (if you move it after mid-morning, you'll be unlikely to find another spot), you can make that a completely free 24 hour period. There are also now parking boxes on some of the streets around the Swisshotel, Fairmont and Hyatt, allowing you to purchase up to two hours at a time (with a credit or debit card) - for, I believe, $1 per hour. I'm not sure whether you can park overnight at these spots - or whether you can, but there is no charge. So, with a little bit of creativity and vigilance, you can park relatively cheaply in this area. Just be very careful. A parking ticket will be at least $50.