Instead of using your pencil eraser to make marks disappear, turn it into a stamp and make playful pictures appear on cards and wrapping paper.
Just press the eraser into an ink pad, and stamp polka dots onto paper. Or cut the eraser with a utility knife to create different looks: Half an eraser makes a half-moon, and a third creates a delicate crescent. We stamped colored kraft paper and blank card stock, and added stems to flowers with a green pencil.
I've only used the whole pencil eraser before, never thought to cut it. Using small polka dots is a great way to add some punch to a Scrapbook Page, add a border of polka dots around a frame or photo, or use random color dots to tie in different hues of patterned paper you might be using.