I've been tracking down the tree of #include statements that bring all the "goodness" into the Arduino environment. I made a mind map of it.
This is an attempt to work out all the built-in functionality that I only seem to become aware of while reading other people's code. "Where did they find that function?" and "how come I didn't read about that in the Reference?" come to my mind often. So this is a start on tracking down all those built-in bits you don't read about on the Arduino site.
That is all.