Any Palm OS hardware
Palm OS 3.5

This program will fill the screen of your palm with red, green and blue colors repeatedly, so you can visually check, if it has some dead pixels.

It's useful to check this out if you are buying used device, or even a brand new one.

Though this test was intended to use on color enabled handhelds, you can also run it grayscale or even b/w devices if you whish. In such case it will simply fill your screen with solid black.