LPT: If you're trying to quit smoking but caught in the cycle of "I'll just finish this pack", take your cigarettes right now while you aren't craving, soak them in the sink so they can't be used, and throw them away.

You may just buy another pack when you crave again tomorrow, but that's fine. After smoking a few you'll want to quit again, so soak that pack too. It's much harder to maintain the habit if you do this whenever the moment of clarity strikes you.