A circular buffer is a really cool fixed-sized FIFO data-structure useful when passing a stream of data from a 'producer' and 'consumer' thread.

It started with an idea: "Wouldn't it be nice to have a search functionality on my blog?". Sure, nowadays there are many libraries and external sites such as Google offering this in some form or other. But, as far as my personal projects are concerned, I am not one to be satiated with a solution that would likely involve said third party injecting hell-knows-what into my little home-brew site. Even if that was an option it would probably be overkill for what I actually need.