Many of you will have read of the tragic fire which destroyed the National Museum of Brazil. Many of the artifacts and documents in the museum were not photographed or backed up, and so are destroyed forever.

This week I attended the "Revolution.Aero" conference on advanced new ideas in aviation, including electric VTOL aircraft (often called "flying cars.") I learned that there's a lot of interesting new stuff going on in aviation, but the strong regulatory environment keeps much of it repressed.

Update 2019: New research suggests the incremental cost per mile of electric robocars is low enough to alter some of the logic below. An update is in the works.

In the world of electric cars, some people talk about an idea called "vehicle to grid" or V2G. Renewable energy's biggest challenge is storage -- wind and solar only come at certain times of the day, but we need electricity all day. The V2G hope is to use all the batteries in electric cars as a means of grid storage.