Just saw this - photobooth for 4 hours for $699, can add on additional hours for $100 per hour.
I'm not conpletely convinced that this is a deep discount deal. While I got married at the end of 2009, my photobooth (Photobooth Express....highly recommend BTW) charged for 6 hours under $1000 with double prints and props. I was able to customize the color of the curtain (which you can see on my profile pic). I booked in 2008 so got those rates.
At minimum, just wanted to pass this along as an option:
http://www.buywithme.com/chicago/deals/8890-daniel-gin-photography