Buy a new pair of workpants on sale a size too small (or maybe 2 sizes) because it will encourage you to shed some pounds.
Three months later when you still haven't lost the weight but your current pair of pants for work are shot (completely and totally... yes, I own one pair of work pants... I'm very frugal) squeeze and I really mean SQUEEZE into the "new" pair of pants that are way too small.
My guess is you won't have as much of an appetite for awhile and you might not use your pockets for a bit. Gah! This is going to be an interesting day. Who wants to take bets on whether or not I bust the zipper today?