Thinking lately about the fact that we have between 300 billion to 1 trillion fucking neurons in our skull.
About the various chemical messengers: Dopamine, Epinephrine, Norepinephrine, Serotonin, Acetylcholine, Histamine, etc...
Funny that the ones I think of off the top of my head are all the monoamines (well except for ACH) according to wikipedia.
Anyways...