Nearly All Binary Searches and Mergesorts are Broken

Here is a fascinating article I stumbled upon. The takeaway for me could not be more eloquently stated than the author's own words:

The general lesson that I take away from this bug is humility: It is hard to write even the smallest piece of code correctly, and our whole world runs on big, complex pieces of code.

http://googleresearch.blogspot.com/2006/06/extra-extra-read-all-about-it-nearly.html