Spent most of last night putting together a small prototype version of my control panel. It's nowhere near what it will be as it's only one joystick and six buttons, but I wanted to try to hook everything up to the I-PAC and plug it all in and see it work. It took much longer than I thought it would for the little bit I did, but it was worth it, and is a fun project. When everything was hooked up I just plugged it into my Mac and it worked! Playing MAME has never been so fun. Here's a pic of the little prototype:

And here's a picture of the guts all wired up:

Since my joysticks can change from 4-way to 8-way I decided to play sevral games of each. The 4-way games work awesome. Pac-Man feels like the original, and there are no "dead zone" areas like there are w/ 8-way sticks. 8-way will take a little to get used to, since the diagonals are a longer throw than the directionals. However, this actually has a slight advantage in fighting games since those tend to use diagonals a lot. It's just that when hitting a directinal, you're used to hitting a litte groove, and hitting something flat feels a bit weird. After a while I got more used to it, though I was still can't do a Dragon Punch in Street Figher 2 to save my life. ;)