I bought some multimedia keyboards online for about $14.00 each. They are "mini keyboards" and look damn similar to the ones in that article.
Its basically the size of a laptop keypad......and its pretty thin....I'm going to velcro mine underneath my CP, its thin enough (and black) that you dont see it.....it has no pointing device on it, but it does have dozens of "buttons" you can hot-link to do things..like auto launch MAME or whatever....I haven't installed that software, but I plan on doing so, specifically to turn on/off the PC remotely and have a 1 button shutdown (if possible)