Give it a try next time you need to mark out some segments on a circle. It looks to be quick and easy but more importantly has an explanation of the math at the end.
A faster, easier way to tie your shoes.
How in the world have I never heard of this? Well click here to watch the video by Numberphile
I just wanted to post this for every one as its a great place to find some free audio books that are in the public domain.
Finding half of any angle – Bisecting
For those that do not know how to find half of an angle here is a very quick way to do so. This comes in handy when cutting trim for irregular angles.