Okay, so I've never seen these, but I had an epiphany a week or two ago and I made one. It's pretty much just tubing running through a big chunk of ice. Smooooooth hits.
I went to a hardware store and found their spools of tubing, and got about 4 feet of the 1/8" tubing (that's inside diameter, I think) and a few inches of 1/2" tubing. Get a jug/bottle (I used a 64oz apple juice jug) and shove the 4 feet of 1/8" tubing into it, but make sure that both of the open ends of the tubing are sticking out of the top of the jug. Also make sure that the tubing doesn't kink up in the jug. Try to get it to coil. Fill with water and put in freezer (making sure that no water gets inside the tubing, just the jug that the tubing is in).
Now with the 1/2", connect this to a small pipe. Slide it over the end of the pipe. I had to heat the tubing up to get my little pipe to fit in it.
Once the jug has hardened, the pipe (with the connection piece) should fit snuggly over one of the tubes sticking out of the top of the supercooler.
Light, inhale, and enjoy.