[jeffbee]

Time travel hasn't been invented yet, but you could still cash-in. Any concrete slab with a big X painted in the middle will work. Get the GPS coordinates of the center of the X. Charge money to stand on the X for 5 minutes and provide an engraved metal tag with the exact coordinates and exact time. When they invent time travel in the future, they will know where and when to look for you.

Reward: The first time someone actually disappears from the X, call me. I'll be your next appointment.