If you are talking about a Python then yes, I have heard of them. In fact, I had one myself a few years ago. Unfortunately these type of cleaning utensils are no good for anyone who is on a water meter because you need to have the tap running to put water in, and also take it out. You also need good water pressure for it to work properly, if your water pressure is weak, it doesn't work very well.
There is also the fact of all that crappy water going into your sink, if it somewhere that you prepare food, I don't think it's particularly hygienic. A gravel vac attached to a hosepipe out of the window does the job for me.