Hal

Hal Varian has the ability to start a discussion off with simple calculations and before you know it, they start yielding important implications and you are discovering deep things. His writeup on Online Ad Auctions (based on the WINE08 talk) to appear in Am. Economic Review is an example. There are simple upper and lower bounds and before you know, they give a way to estimate the value advertisers get from sponsored search, which is nifty. One has to distil the discussion to its simplest and no harder, and still communicate a technical nugget the readers/audience can take away. To do that, one needs to really understand the math and the mechanisms. It is fun to watch!

ps: In a different vein, here is a video in which Hal does community service and explains basics of ad auctions.

pps: Some time ago, Hal was the speaker over a dinner I attended. It is difficult to give these talks to people distracted after a long day by the food and the drinks. You have to abstract a novel concept and still be technical so the audience can walk away with enough to reason about a nugget later. He spoke about his idea of the "combinatorial innovation" in detail.