The second part of a three part neuroscience tutorial has just been published on kuro5hin.org. While the first part covered the basic physiology of the neuron and how signals are generated and propogate within them, the second part deals with how signals are passed between neurons, over the synapse.
The synapse is the principal part of the neuron where neurotransmitters are released. Because of this, it is where most psychoactive drugs have their effect, which often work by mimicking or altering the normal function of neurotransmitters as they communicate signals throughout the brain and other parts of the nervous system.
Mind Hacks 
Another omnibus
Short lessons: – How neurons transmit information, part 1 and part 2 (part 3 coming soon) [via Mind Hacks] – A Cartoon History of Iceland [via TMN] How we work: habits, rituals and methods. [via Things] Team B, take 2…