My Mb sits next to my TV, is controlled by my TV/DVD/Stereo/Mb universal IR remote, can play Internet radio stations, MP3s, AVIs, show info from the web, and sit there just as a low-power, full-time, file share.
Step 1: The Guts
The mobo's overall size is about 6-3/4" square which happens to fit nicely on top of the power supply.
The IR receiver module is epoxied to the inside of the front panel. The IR sensor of the receiver module sticks through a hole drilled in the panel.
I put an acrylic sheet between the mobo and components on the back for electrical isolation and some structure to mount things to.
The USB/WiFi adapter is zip-tied to the acrylic sheet.
The harddrive is bracketed to the mobo and power supply using hand cut and bent sheet metal brackets.
The front panel USB connector is epoxied to two small wood blocks and the front panel through a square hole in the front panel.
The LED is hot glued into one of the grill holes in the front panel.