Find Muck
I've watched a bunch of clips from the TED converence. From what I've read and seen it looks like a real mind-blowing conference. In an environment filled with intellectuals and creative geniuses, it would be hard to critique the information delivered, let along provide any sensible ranking.
Nonetheless, when I watched the presentation by Vilayanur Ramachandran, I had an immediate favourite.
Naturally, my opinioned is skewed by the fact that Ramachandran's presentation happened to include topics I already find fascinating: synesthesia, creativity, and the connection between awareness and emotion. The clincher for me though, was the investigation based on brain defects - the idea that if we have cases of brains with sections that are not functioning properly, than we can deduce how parts of the brain contribute to its overall function. I am constantly aware of the effect of my own, relatively minor brain damage, and this line of reasoning really strikes a chord with me.
Additionally, Ramachandran's delivery is so captivating yet unorthodox, confident yet humble, it's hard to look away. I particularly love that classic Indian trait of meticulously clinical and calculated speech.