I have had no problems overheating, I didn't post a pic of the bottom of the box, but I drilled a series of vent holes underneath the CPU, as well as a slot in the front that doesn't appear in the pics. I am using a 3" 12v exhaust fan, don't remember the RPM offhand, but it's pretty meaty. Maybe if you folks want I can take a few more pics of the vent system and post them later today when I am done with appointments.
I admit I had some help with the woodworking, my inlaws have a wood shop in the basement, so they helped with stuff like planing the rough wood and biscuit joining. I drew up the plans using Corel Draw, and then rendered an image to scale in Maya. Took that to the shop after I loaded two 5' boards into my tiny Celica.

As far as the price, it wasn't really all that bad. The entire 10' board cost me 82 bucks, not sure what is was listed at in boardfeet. I was toying with the idea of making these for sale, but I doubt anyone would want to pay enough to cover costs and labor. I could cut down on cost by using veneer, or by using curly for just the top and oak for the rest, but what fun would that be?

*edit* Actually if you look close at the uncoveredfan.jpg, you can see there's a gap under the front control panel top. I am going to cover this with the same brass mesh used to cover the fanhole, and use it as a place to possibly mount a powered USB hub, after I find out how to splice it into the existing PSU. That will let me do stuff like easily plug in a racing wheel, gamepads and the like.