Re: Alcohol in base?! Sounds dangerous to me!
If you want to try alcohol in the base, try diluting it.
Folks who think you get only very little alcohol...well perhaps...however unlike drinking alcohol, when you breath alcohol vapor, it is absorbed almost instantly into the bloodstream. The only faster method would be to inject the stuff intravenously.
When I was first starting out we got the idea to put straight vodka in the bottom. It was a bit (ok a lot) harsh, but all of us were feeling the effect in minutes.
If you want to do alcohol in the base pick something that complements the flavor in the top, and don't use it straight.
AF Two Apples up top, for instance, is quite good with about 5 parts water and 1 or 2 parts Jagermeister or other anise/licorice like liqeur. Absinthe even works.
Delicious...and not overpowering.
Incidentally I read somewhere some of the very first hookahs had all sorts of exotic things put into them (wine, pearls, etc etc) for various reasons often having little to do with taste...it wasn't until tobacco from the (then) New World became widely available that hookah took off.
Or so is my recollection of what I read.
Straight vodka or everclear (or other pure grain alcohol) is not a great idea. It'll smoke harsh, even if the alcohol just came from the freezer, it will overpower whatever flavor you're trying for, and even though it's not as much as drinking, it is going almost instantaneously non diluted (the vapor is pure alcohol) into your bloodstream via your lungs. You'll be drunk before the coals burned out, and drunk people + burning coals + base full of pure alcohol=trouble.
So...if you're going to do it, dilute, so the water can do some work, and you can still enjoy the flavor.