The aforementioned Chicken Unlimited in Eau Claire WI has been closed for over a year; it was supposed to be sold and reopened but evidently that fell through back around Jan. of 2012, then it was sold to a new owner who was planning to reopen it as an Italian restaurant but that has not happened as far as I know.
As for the Chicago-area locations.... Some months back I made it my project to see what has happened to all those 90+ locations. Many (probably close to half) are still standing and they are now in use in a mind-boggling array of new businesses. Obvious among them are restaurants (numerous Chinese, Mexican, subs, chicken, hot dogs, pizza, gyros, pitas, etc) and many other types of businesses - a couple banks, several currency exchanges, insurance offices, a muffler shop, a Christian bookstore, a massage parlor, a dentists office, a hair salon, a photography studio, a bar... I'm sure I'm forgetting something. Sure makes me sad I missed ever eating at one. The Chicken Unlimited I used to see as a kid is now a Subway.