[Animats]

"I can't really think of somewhere in Silicon Valley (or near by) that has the lack of population, lack of airspace traffic, and lack of local / state / federal ordinances that would allow this degree of freedom."

Southern California has Mojave Air and Space Port, which is, among other things, a flight test center for civilian aircraft. Scaled Composites flies from there, and SpaceShip One was launched from there for the X-Prize. They have a test pilot school. Lots of exotic aircraft activity takes place there. Read their "Why Test Here" section.[1] Three of their features: "Welcoming attitude toward imagination and experimentation", "Huge airspace away from populated urban areas", and "Should you ever need it, a sophisticated Aerospace Rescue and FireFighting operation". This is useful for larger or longer-ranged drones. QF-4 drones, converted from F-4 fighters, are built and tested there.

[1] http://www.mojaveairport.com/why-test-here.html