Very strange about that video. I can watch it (when I type it in). But it doesn't work when a copy and paste the link here? Weird. Anyway, it can be found by typing "1913 Etrich Taube Aeroplane" into the YouTube search.

What's interesting is that the inspiration for the wing-warping apparently came from a seed-pod rather than the more obvious fact of how birds use their wingtip feathers.

Here's a nice RC version:

[youtube]http://www.youtube.com/watch?v=GhUp1LCw2cg&NR=1[/youtube]