Resin is actually the trichromes used for making hash
(simply put), residue would be more accurate for the tar and build up that you find in your pipes, bongs
, bubblers- anything you smoke creates a black sticky substance that unfortunatly I have much experience smoking. Read below for tips.
Disclaimer: May not be legal in some countries (imagine that)
As a heavy smoker, there is usually bud around, but when there is a drought and I need to keep the edge off resin will do the trick though the buzz is more of a body buzz in my experiences and tends to be more subtle yet still a good buzz, laid back- kinda hard to explain.
There are a few tricks to smoking and collecting resin and if you don't know what you're doing you will end up with resiny tar everywhere and few things can get it out. First there are 2 main methods- smoking it directly from the pipe or collecting it by scraping your smoking utensils.
Smoking out it from an unpacked bowl is simple, either smoke as you would a normal bowl if there is enough buildup inside or hold the pipe sideways and use the bowl as a carb and light the flame from the real carb breathing in slowing from the mouthpiece. Heating the resin is important and stop if the smoke is too hot.
When you're really desperate you can do as I do and take every piece with resin in it, get about 3-4 large paperclips, a place for the resin collected (cellophane from a cigg pack works) and get ready to get your fingers dirty. Heat all bowls enough that the resin starts to smoke before scraping. Be careful with the paperclips and bend them to get the best angle for your bowl. Keep adding the small amounts you get till you have a nice marble sized ball, let it dry a little then smoke it and be prepared to cough. Best smoked out of some sort of pipe with a screen to prevent it all from melting back into the pipe.
Anyways, hopes this helps, and remember resin smokes a LONG time and is easy to get a good deal out of even small bowls but as for your health... I'm still good after 4 years of near consistant smoking (all types) Doc says I'm in great shape... hope it works out that way for you too! Happy Tok'n!
(For liability sake, this is all hypothetical ;-)