I hadn't used my scale for a long time, then I joined Ediets to get rid of those stubborn 10 poundes I'd gained and couldn't get rid of. I got in the habit of weighing in once a week, and it keeps me "in line." I use the weight as just one more statistic, not as the only measure of fitness or health or being in great shape. If the weight goes up without my doing heavy lifting AND I notice things like my size 8 pants are tight, then I might add some more cardio into my routine or look at what I've been eating and see what extras I can cut back on.
I did donate my dial display scale to the Salvation Army after getting a more accurate digital scale that weighs in half-pound increments (even though the new one "says" I'm 3# heavier than the old one!).