I was watching Dark Knight (The new batman Movie) last night, which was filmed partly in Chicago, and there is a scene where Batman is standing on top of one of the roof decks on the Sears Tower (North Side of the tower). In that scene you get a great shot of the antenna mounting grid with all the fiberglass sticks and one lone DB-420 (or what looks to be one) on the corner right by Batman.
Kinda neat to see- just be careful when you pause it to see- Your significant other may roll their eyes at you! At least mine did.... Tom W9SRV