Done correctly this is a mind-wiper. I've done this as part of a mostly-mentalism act for a 30
person audience and left them stunned. Take your time doing the business while asking the audience
to calculate how many minutes are in a day, and then in a week (10,080!). Make them actually
calculate the number using cell phone calculators if necessary. You can do what you have to do while
talking with them. Then do as others have suggested... have a sealed envelope in view from the
beginning, open it and remove a SMALLER sealed envelope and hand it out and have someone else open
it to remove the photo. I use Kaylor's UCCU to help with this final step, and the result absolutely
slays them.