I thought I would share this website I found with a little googling while I was visiting Chicago recently.  You can use it to find cheap parking in Chicago, which is particularly handy downtown.  Ladies who are visiting or who host downtown, you can even look up the best reasonably priced parking near your Incall and suggest it to gentlemen who may be visiting you.  There are similar websites in some other cities and they've been helpful to me in the past.