Built with MDF wood with 1x1 struts for support in the corners. The control panel was built with parts from Happ Controls, and an X-Arcade control board with a Dreamcast adapter. I was going to hack a couple of controllers, but didn't feel comfortable enough in my soldering skills (or lack there of). The controls work great. The only downside to this method is the loss of memory card functionality. To resolve this, I took apart a DC controller that no longer worked. The controller still read memory cards. I took out the circuit board from the controller, built a box around it with a hole exposing the memory card slots. This is plugged into port 3, giving me access to memory cards on that port.
Took about 1 week and a half, and cost was a little over 400 bucks (And that includes the 19" TV and Dreamcast that I already had). I know it doesn't add anything cool to what the DC already does, and it really isn't a mod to the DC itself....but it sure looks good in the game room and is a heck of a lot of fun to play Street Fighter 3 on real arcade controls
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My life is full of disappointments 
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