Status Bar Messages
Nice and simple one this, the script has 2 functions using self.status() to display and clear the status bar of the browser. Although these are single line functions, you could make them more useful for displaying common messages or prefixing text.
Use the functions in combination with DHTML commands such as onFocus to display help messages (or anything else for that matter!) in the status bar of the browser.
Example
Click on the Reference field to see the help message. Click anywhere else to clear it. Use your browser's 'View Source' command to view the example code.