This is a coffee table I made for Anna. The whole idea wasn't mine, but I chose the junk to put in the boxes. The original (as far as I know) resides in the Diesel Coffee House in Davis Square.
On the image below, you can click on a box to see a closeup of the contents.
These are some pictures of the table during the building process.
The outer ring of 4" square light-switch boxes. I used 8-32 nuts & bolts to connect the boxes (plus lock-washers).
The complete array of boxes. It definitely helped to leave some of the nuts & bolts loose while arranging the boxes and tighten them later. All the boxes are facing the same direction (not because I'm anal, but because the holes are positioned differently on different sides of the boxes, and putting them all in the same orientation makes the holes line up nice).
A closeup of one of the boxes, empty.
A closeup of the hardware used to attach the legs. This view is of the bottom of the table. I guess I lucked out in that the holes happened to line up with some on the bottom of the boxes.
The table, with legs attached. The legs were 1/2" diameter, 18" long threaded pipe.
The finished table. Note that the plexiglass cover extends a few inches past the metal on all sides. Be sure to sand the edges 'cause they're sharp!