Ben-lamp is rail and stile construction. I used a combination of router and table saw, depending on what was going to work best.
WoodJitzu-I do not have a photo of the bottom, but I can describe it. Top is fastened, so the light fixture is maintained from underneath. In other words, the entire light fixture can be removed from the piece. I went simple. The fixture is fastened to an oak cutout the fits the bottom precisely, with some wiggle room for expansion. I drilled two holes on the inside bottom of lamp rail, which then receive a round mini deadbolt latch (2). The two latches secure fixture to the piece. Light bulbs are very easy to change, as you simply release the two latches and the fixture pulls from the bottom. I hope that helps.
I just love your lamp.
In fact I love it so much I am attempting to copy your style but put a computer in it instead.
It will need to be a little fatter but I hope it doesn't destroy the look, it is just so nice.
Hope you don't mind.
Here's where I'm at right now.