This afternoon I broke in my new Vibram Five Fingers that I got for $40 shipped from woot.com a couple months ago. I have worn out my old pair that cost over $100. 

The first run in these is a little uncomfortable, but I made it over 4 miles. They should be nice and loosened up after a couple more runs. 

If you've ever considered running in them, only do so if you land on the balls of your feet when you run. If you run with a normally heel strike, you could do major damage to your heels and legs. I've always walked and run on my tip toes when I'm barefoot (around the house) so these shoes felt very natural to me.