Click to Listen Mac OS X Leopard has the coolest new feature I've ever seen in an operating system. It's called Quick Look. What quick look allows you to peek inside of a document, video, audio file, and several other file types. Before Leopard, you would have to double click on a file, launch the application to view it, see if it's the file you were looking for, and then exit the application. If you are looking for a specific document, this is really time consuming.
With Quick Look, you simply need to select a file, then press the space bar, and if Quick Look understands the file type, it will show you a preview of the document, video, or audio file. You can browse documents and even play the media files right from the Quick Look preview. If you use Quick Look with the Cover Flow view, it makes for a great combination, and you will soon discover it's power and change the way you look at files on a daily basis, and make you wonder how you ever got along without it.