Making objects slide

I'm trying to make a skiing game where the character will need to slide, the problem is the character is doing anything but that. I'm using the basic rigidbodyFPSWalker script from the wiki and once I let go of w,a,s, or d the character stops moving. I tried making friction 0 and mass 0, but that did nothing. To see if the script was the issue I placed a simple cube with a rigidbody near a cliff and used the character to push it off, after a few seconds that cube slide to a stop too. Is there a way to make rigidbodies slide? I'll need to have the character not only slide going down a slope but also when it tries to go up one too steep and slides the opposite way.