You can add multiple desktops to the Mac OS X Mountain Lion by using Mission Control, formerly known as Spaces. Can be really useful if you are a busy multi-tasker.
If you like the Lords of the Rings movie trilogy, then you might also like this Photoshop tutorial, where we will make a dramatically red sky on a random photograph.
A real useful web service for all the designer who want to know what colors have been used on a certain image. You can even download a Photoshop Swatch file containing the color palette of the image.
As you probably noticed on a lot of websites these days, there is an engraved looking effect added to text, let me show you how to add that effect using CSS.