fwiw rubbing alcohol and sea salt works really good for a cheap solution. Put some sea salt in your pipe and then put it in a plastic air tight container that has rubbing alcohol and some more sea salt. Close the container (you could use tupperware) and shake until the pipe is clean.
let peice run under hot water for about a minute, then get 2 sandwich bags, some 90+% Alcohol, and put peice in bag with rubbing alcohol in microwave for about 10-15 sec, take out and shake the shit outta it....take out and rinse with hot water
But Grunge Off is better. Biodegradable, all natural, reusable, soak. Not zip locks and shaking your pieces around to get the salt to scrub. Just soak over night when you go to bed, and rinse with hot water in the morning. No scrubbing needed.
Even quick 10min soaks get the majority of it. The rest can be whipped away with a qtip