FolderGuard for Mac

From MacZ Software:

FolderGuard is a password-protected shareware utility designed to protect your private folders and the files inside the folders from for example nosy co-workers. FolderGuard automatically maintains a list of folders. The folders in that list don't have to be hidden to be listed in the folder list. When you want to make a folder visible or invisible, just select it and click "Toggle visibility". FolderGuard is quick and easy to use. All you have to do to hide a folder is to lauch FolderGuard, type in your password, add a folder to FolderGuard's list and make it invisible by clicking a button. FolderGuard is also easy to set up: the setup assistant helps you set your preferences when you first launch FolderGuard. The application supports drag and drop, so you can add folders to the Folder Manager list simply by dragging and dropping them into the Manager window from the Finder. Folders can be added using a traditional folder selection dialog as well. FolderGuard automatically saves your list of folders so there is no list saving to worry about. The program displays invisible folders in italics and visible folders in plain style in its list. There is also an info bar at the bottom of the main window displaying the name and visibility setting of the selected folder.