I've had a kind of fetish for
Dixie Square Mall since I accidentally discovered it (don't you love getting lost in the "blue" of Wikipedia?) a couple months ago (and thus, the idea of "urban exploring").
To condense the history for ya, Dixie Square Mall is an abandoned mall outside Chicago that has been closed for thirty years (which is more than twice as long as it was open). It was used in the first Blues Brothers movie (the producers dressed the then-recently closed mall to make it look open, including a Pier 1-- SQUEE!).
This is one of the better videos I've seen:
Click to view
And the scene from the BB flick:
Click to view
Does this weird stuff interest ya? Check out
abandonedplaces.