I was just released from prison on December 18, 2009.  During the period ending about November 4, 2009, I engaged in a 101-day hunger strike.  (Actually, 100 and 2/3 days:  Started 221 pounds, ended up an estimated 171 pounds).  Generally, I drank two cups of milk in the morning, and drank water as needed.  I was never force-fed.  Nor, oddly enough, was I ever hungry, or in appreciable discomfort.  I was examined, almost daily, by prison medical staff.  Probably the reason that I did so well was that I understood that the most important thing is to maintain the body's electrolytes (calcium, potassium, sodium, magnesium, phosphate), and to consume just enough amino-acids to supply neurotransmitters. (If you merely drink water, after a couple weeks you'll lose enough electrolytes to cause an imbalance, and you'll feel terrible.  Most people attribute this to not eating, but I learned that it's actually due to the electrolyte imbalance, NOT the lack of calories.)  At the time, the longest hunger strike I'd ever heard of was referred to in the Capote book, "In Cold Blood", by Perry Smith, in the early 1960's:  93 days.  I could probably have gone two more months.