These work on Mac or Windows in InDesign 2.X or CS:

Bounce: Choose "About InDesign" from the menu, and when the splash screen comes up, type BOUNCE.

SVG: Same as above, but instead of typing BOUNCE, type SVG (Adobe's interesting vector/web image format)

Rainbow: Choose Stroke Styles from the Stroke palette menu, and create a new striped stroke. It doesn't matter what it looks like, just make sure to name it "Rainbow." Apply the stroke to an object.

Feet: Create another stroke, but this time choose a Dashed style for it, and name it "Feet." Apply it to an object.

Thanks to Sandee Cohen (InDesign author extraordinaire) for letting us InDesign listserv subscribers learn about the last two!