I just found myself describing how I keep pipes and bongs clean and I thought "why not post about this." Here we go. We all know that cannabis is about as harmless as anything can get but that doesn't mean a dirty pipe can't get you sick. I have personally seen this happen to someone and they were sick for a month with a terrible pneumonia. Plus resin tastes bad and can make your smoke out less enjoyable. The solution is simple. Keep your pipes clean.
I know resin is a bitch to clean but I am going to share a method that works better than any other that I have tried and even outperforms store bought bong and pipe cleaners. Better yet, it is cheap, simple, and easy.
All you need is some powered dishwasher detergent, hot water, and a piece of wire from a notebook.
Simply fill a large container with very hot tap water and a generous amount of the powered soap. Stir it to insure that the soap doesn't all collect at the bottom and completely submerge your pipe. Let it sit for several hours and rinse thoroughly. This will remove 95% of the filth (sometimes a second soak is required if the piece is really dirty). Next shape your wire to reach the inside of your pipe and remove any specks that are left. Lastly rinse again and dry your pipe.
Now you have a clean pipe, you don't have to worry about getting sick, and your weed will taste better.
I have never seen this method harm the color or fuming on the glass but as with anything proceed at your own (pipe's) risk. Just don't be too rough with the wire so you don't break your anything.
Have fun everyone and be safe.