Launch iMedia Browser, and its toolbar displays icons for Photos, Audio, Movies, and Links. Click an icon to view that type of media:

Click on a source or folder in the top pane of the window to view the contents of that source in the bottom pane. For images and video, you see resizable previews; double-click a photo to view it in Preview or a movie to play it within the iMedia Browser. For audio, double-clicking a file (or selecting it and clicking the large play button) plays the track, although I wasn't able to preview GarageBand projects. For Links, double-clicking a bookmark opens it in your default browser; unfortunately, you don't get a textual preview of a bookmark's URL.

For photos, audio, and movies, you can drag additional folders into the browser to make those folders' enclosed media available for browsing. There's also a Search field that lets you quickly filter your media.

Once you've found an item you want to share or use elsewhere, simply drag it from iMedia Browser to an e-mail message, into an iChat window, to a folder or volume in the Finder, or to a program that accepts media (such as a Web-design application); the file will be added as an attachment, sent, or copied, just as if you'd dragged it from the source program. (The exception here is bookmarks; the Links view is provided mainly as a way to quickly access your bookmarks. It would be great if you could drag a bookmark to, say, an e-mail message to include the bookmark's URL in the message.)

You can choose for iMedia Browser to act as a normal program, or to hide when in the background; if you enable the latter option, you can access iMedia Browser from either the Dock or the menu bar. I keep iMedia Browser running all the time for quick access to my media.