Truly amazing work by the NYC Grid guys creating images composed of two images at the exactly same location only decades or sometimes even century apart.
If you are more of a visual person and would like to organize your folders and files using different colors, than check it out how to use color labels in Mac OS X.
A less known but very useful feature that works since Windows XP has been released. You can easily rename a bunch of files in a matter of seconds, let me show you how.