I heard the podcasts about micro communications and the secret of a great handshake and both fit in an area I'm very interested in and that has brought me great results: body language.
The thing with body language is that we all know it. We can all say that we felt uncomfortable by someone's handshake, posture, etc, but we don't quite know why that happened. Understanding body language is not about being able to "read" other people but more about to be able to pass the right signals and understand the disguised and often unconscious ones. That's why a smile is so important!
About the handshake. I believe that the podcast is fantastic because it teaches what to do. But why do people react well to it? First, because we enter the other person personal space without invading their intimate space. Mark mentioned several "moves" people do when handshaking, most of them invade the intimate space, like shoulder movement and using two hands to sandwich. Second, our hand is not palm up (which is perceived as reverence (sp?)) or palm down (which is perceived as arrogance, like a king or a godfather). Think of the kiss of the ring and how both leader and follower behave in it. The only thing I believe wasn't mentioned was extending the fingers and touch the wrist. Again, that is an invasion of intimate space, so it will be uncomfortable and therefor perceived as unprofessional.
About the micro communications. I could write for quite a bit about that but it all boils down to how we open up to the other person in terms of the podcast. All mammals expose their belly when they are interested, available, calm and trustful. If you ever had a dog you know what I mean. If we want to show interest to what someone else is telling us, we face them and don't cross our arms or legs. Their limbic system will immediately read "he wants to know what I have to say". Even if you don't, doesn't hurt to be polite on a unconscious level. This is exactly what Mark mentioned when mentioned the perpendicular of his shoulders with the person he is speaking with. Smile means we are relaxed, nodding means we are listening. Works like a charm and opens a big door when we have to say we don't agree because it won't be taken as hostile.
Last but not least, look at their feet. If one or both of their feet are pointing away from you, that is the strongest non-verbal indication that the person you are speaking with wants to be somewhere else. It doesn't mean you or what you are saying is not interesting but at least it is not as important as what that person needs to address somewhere else.
If you find this interesting for your professional (and even personal life) I'll be more than glad to give easy tips, point to books, etc.
Hope it helps!