Prox Dynamics' PD-100 "Black Hornet" nano-copter has already gone through a number of different prototypes and test flights, but it looks like things have really started to come together with the last few models, and the company has taken advantage of the opportunity to show off their progress in a couple of videos. One of those shows a "simulated" indoor mission, in which the 15 gram copter scouts out a nondescript office building whilst some suitably dramatic music plays in the background. The other, slightly more interesting video demonstrates how the two latest models are able to handle themselves in flight, and hold up against some obstacles, like the always problematic flapping cl