OK Ladies and Gentlemen, it's time for the big one - Yom Kippur. That's 25 hours of no food or water, not to mention focusing on sin and personal shortcomings. Yeah, it's fun.
Check out this interesting series on one Woman's search to figure out if she should fast or not. Careful - I've only read the first few installments, so I'm not sure it's completely appropriate. Though I've been both entertained and educated by what she has to say.
Whatever your reason for fasting, I wish you an easy and meaningful one.