http://www.scribd.com/doc/95722979/Starving-Your-Way-to-Vigo...
After reading that article and doing a little bit of further research online, I tried a pair of fasts. The first was a week, followed a few months later by one of 10 days. My experience was very similar to what the author describes. That is, I felt good during the fast after the miserable 2nd day. Coming off the fast was no problem, either. Food was actually not a significant temptation during the fast and I found the discipline aspect to be much easier than the couple of standard diets I've ever tried.
I'm tall and about 50 pounds overweight (~200 lbs would be my target weight). In the 10 day fast I lost roughly a pound per day, but for me the weight came back within just a few weeks. I suspect that to have the best results I'd have to continue my fast for 5-6 weeks.
In fact, I only broke my fast because I was leaving for a road trip vacation in which I had to drive. My focus was actually fine and I was able to write software with no problems during my fast, but wasn't willing to experiment with long stretches of driving.
I'm actually looking forward to my next fast which I hope I can make last at least several weeks.