Originally used to refer to:
* Chronic hash or opium users.
* The specific practice of injecting a combination of heroin and (freebase?) cocaine.
* A way of smoking heroin using aluminum foil

ChasingTheDragon is a good metaphor for those trying to find a SilverBullet - whether by formalizing patterns, developing a one-size-fits-all methodology, writing a perfect language, etc. It's a near impossible task, but many keep trying in hopes of reaching a transcendent state. 
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CategoryMetaphor