The resin left in a cannabis pipe. When in abundance, the resin can be collected and smoked for a good buzz. This is usually an alternative when one is out of cannabis to smoke.
When cannabis is combusted in a pipe, some of the various Cannabinoids stick to the sides of the bowl in a sticky resin. When smoked, this resin, Black Buddha produces some very similar effects as flower-form cannabis.
Stoner 1 - "Emergency bro! We are out of weed!"
Stoner 2 - "Not to worry dude. Take out your pipe and scrape up some Black Buddha!"