Instant Dictionary Keystroke in Safari for Mac: Control-Command-D

Here’s a very useful key combination that allows you to instantly summon a dictionary from the web browsers in Mac OS X.
If you’re in Safari (and many other Mac OS X apps and browsers), hit control-command-D keystroke together while you hover over a word, a dictionary will pop up with that words definition!

If you own a Mac laptop, you’ll want this great app. CoconutBattery provides the usual current battery charge information, but that’s not what makes it cool. 

Pacifist is one of those really useful apps you wish you had that you didn’t know existed. Pacifist is a shareware application that opens Mac OS X .pkg package files, .dmg disk images, and .tar, .tgz, and .tar.gz file archives and allows you to extract individual files and folders out of them. This is useful, for instance, if an application which is installed by the operating system becomes damaged and needs to be reinstalled without the hassle of reinstalling all of Mac OS X.