this was my first attempt, a gutted atari dig dug/centipede style cab:

and this is my second and most recent:

actually spent a few bucks on the frogger art!
i think both of mine are pretty tasteful, if more people did this at a minimum and spent a few minutes planning before diving in, MAME wouldnt have such a bad name.
this was my first mame test rig when i was learning how to hook up the buttons and joysticks:

eventually i built a pair of these, and by then i realized there was no way to duplicate the feel of an actual arcade game without building or modifying an actual arcade game. these were hooked up to a laptop and then into a big screen TV and could be played sitting on the couch:

i didnt do anything pretty, but i took my time and did my research and didnt go off half cocked. its not rocket science.