hahah, love this thread. Some things I have heard that worked for others I've talked to at my clinic:
Make a bead necklace out of silver lead fishing weights, the oval kind. You can add 3 lbs. with that.
Fishing weights in your pockets or attached with safety pin to the inside of your clothes.
When they get your height, don't stand straight. You can take off 1/2 to one inch easily, which can be the difference between making the cutoff or no.
Right before you go in, drink Water. A 16oz bottle of water is 1 lb.
A few days before you go in make yourself constipated - no Fiber and lots of cheese and potatoes. You can hold onto several pounds of poop when you are constipated.
Eat Chinese food the night before and drink lots of fluids but no caffeine. The sodium content will make you hold water. Caffeine is a diuretic - makes you pee, and that will get rid of all the water you are trying to hold onto.
Now if there were just a way to take off weight that easily!