Well, I just did an experiment where I rigged my e-cig up to my ..... The vapor does pass through the water, however you lose about 50% of it at least. Smoking a regular hookah however is already vaping though. For those of you who don't know how a hookah works, there is a large vase and at the top there is a bowl. You put the shisha (flavored tobacco and molasses mixture) in the bowl and cover it with tin foil. You poke holes in the tinfoil to allow hot air to pass through, and you put a lit coal on top of the tin foil. When you inhale, you draw the heat from the coal into the bowl which vaporizes the shisha. From under this bowl a tube goes down through the vase into the water. It then is drawn through the water as you inhale on the hose, which is connected to the vase base above the water-line.
I actually made an improved version which insures that the shisha is completely vaporized without any being burnt. I wish I had a picture of it but the set-up I made broke and I never felt like making it again. I took the bowl off the top of the tube. I then took an Erlenmeyer flask (the cone shaped kind) and attached one side of a hose to the top of the Erlenmeyer flask and one side to the top of the hookah tube. I then built a small platform on top of the hookah where the bowl would have been and attached a tomato can and cut it down to about half it's original height, put slits on the sides and then placed the Erlenmeyer flask on top of that and secured it in place. The hot coal goes in the can, and a 1-2cm layer of shisha is spread evenly at the bottom of the Erlenmeyer flask. The heat from the coal beneath the Erlenmeyer flask heats the shisha and causes it to vaporize, the vapor is drawn out of the top of the flash and down into the hookah, and then through the water, into the hose that you're inhaling on and into your mouth. If anyone is having difficulty understanding what I was trying to describe I could do a drawing/diagram on the computer.
