I have this crazy idea to build a large playing table out of these crates based on a Courscant or "Fith Element" New York where I stack these things rougly table high and then build buildings on top of the platforms. I'd make some fo the platforms different heights and some of them would be connected by "tech" bridges and walkways while some would be isolated. To complete it I would paint a drop cloth like clouds of polution so I could get some awsome top down photographs.
Could also be done on a table with fluffy wads of cotton and fewer crates.
Reminds me of the Crimson Skies demo I saw; tall skyscrapers bisected by a sheet of plexiglass, marked in hexes, which acted as the play space.. It would be pretty easy using crates, now that I think of it. Especially if you have most buildings 'end' at the plexiglass, and the lower 'canyons' too narrow for planes. Then, just a few building tops to act as terrain.
Doug