The real quote is a Chinese proverb that says: "Give me a fish and I eat today; teach me to fish and I eat for a lifetime."
It is always best, in my experience, to show someone how to do something, but not to do it for them.
"Fish Slap" has become a metaphor in the blogosphere, from whomever started it — I can’t find an attribution. A “fish slap” is a mash-up of the Monty Python skit and the proverb. So, if someone gives you hints about how to do something, but does not tell you how to do it, you can give them a fish slap. i.e., you did not hand me a fish; I figured it out myself!
Here’s the fun Monty Python bit: http://video.google.com/videoplay?docid=-2002541459944162494
But if you aren’t a Monty Python fan, just remember the proverb.