Or make writing appear on the paper. Many other possibilities. An initialed dollar bill vanishes and is discovered in a locked tube. Professional brass version also available. These approximately one inch balls multiply, and vanish.
Many effects are possible.
Larger, wooden Billiard Balls are also available. A classic effect used by professionals and beginners. A borrowed dollar bill is folded up in a piece of paper. This piece is folded in several other pieces of paper. Also make writing appear on blank paper.