I posted this in this week's running thread, but I'll add it here too:

I've been experimenting with some barefoot running on the treadmill lately. This is in addition to my attempt to learn Chi Running. I started with just a couple of minutes to allow my body to get used to the new workout. Now I'm up to 0.75 miles at a time.

I'm still getting little hot spots on the balls of my feet, which I attribute to soft skin that needs to toughen up, and some soreness in my calves and ankles. However, I'm amazed that I have a lot less hip and knee pain! And it's an immediate decrease- I take my shoes off and my IT band and knee feel better almost instantly.

I can't explain what I'm doing differently while barefoot, compared to shod running, but it's been enough to convince me to buy a pair of VFFs when they come back in stock.