Scales are definitely funny things.... I weigh myself daily first thing in the morning as a tool to monitor my body's reactions to certain foods (or to spot lapses in my eating behavior!), I chart this daily in a spreadsheet and as long as the overall trend is downward movement, I don't sweat the little ups that come with the downs. I've just ordered a new digital scale and hope that it will be more accurate than my current one which weighs 6 lbs light (little depressing to add that 6 to the total).

I agree with kj, about not getting too hung up on the scale though...even though I weigh everyday I also measure monthly. Muscle make a huge difference. I weigh about 175 right now and am wearing 9's and 11's. The last time I weighed 175 I wore 2 or 3 sizes larger, but the weight training I do has made a big difference in my body composition.