Ive used a PCI USB card to ad more USB ports, My internal USB pin connector ports run flakey so I dont use them any more,
I also run a 4 port USB internal hub, mounted to the front of my tower, as well as a multicard reader.
USB wireless Mouse and Keyboard
USB touch screen and a neat Powermate thats a volume control.
My Touch screen and external USB hub is 20 ft away from my Media Center PC via two USB 2.0 certified cables, that is allso hooked up to my PLASMA
Paying for USB cables of quality is helped me out, the cheap ones just didnt work out for me