Use your Palm as a torch or a mirror!
Torch clears the screen and sets the backlight to max. (after exiting it sets the background value back to normal level). In the dark it can be used as torch. Its second use is to set the background to black, so you can use it as a kind of mirror.
This simple and free piece of software won't take up much room on your Palm, but could very well prove to be invaluable!