I have liked a lot of things as thank-you or acknoledgement to the author. If I want to make something known, if I want to spread the word, I clicked the "share" button, that was its purpouse.
You can send a message to the author if you want to acknowledge something privately. The +1 button is there to make it publicly known that you endorse the content, that is its purpose.
It's hardly a canonical source, but very much on the 'seemingly magical' side of things -- there's a Twitter account devoted to crawling old boards and pages and tweeting interesting snippets.
The reason the standards don't speak of 2D euclidean geometry is because they (Very sensibly, IMO) left room for yet unknown devices that might not fit that description but still are able to conform.
Flies have an exoskeleton which, unlike the quadcopters of our engineers, have many flexible parts. This is much like the cage only in a very different configuration. I don't know about the wings in particular, but I can imagine they are more flexible than brittle and may even be capable of growing scar tissue.
