I honestly thought that this would not work because it is way too simple and easy for me to be the first person to think of it. (or at least the first person to publish) A normal scuba light will run you about $100-$150, renting one usually goes for between $9-$15.
I made a video podcast for the project below.
Please check out my other instructables as well.
LED Flashlight (I got 3 for $9 from Home Depot and made 2 dive lights) The lights should also have a push-button switch with a rubber seal and rubber seals at the threaded joints.
A drill with a small bit (I used a 3/64")
A small tupperware container
A small bottle of mineral oil (its a laxative so get it at a pharmacy for a few $)