Fingerpaint
Fingerpaint is a kind of paint intended, as the name suggests, to be applied with the fingers; it typically comes in pots and is used by small children, though it has very occasionally been used by adults either in teaching art to children, or independently.
Fingerpaints are often used on a paper specifically produced for the purpose.
Fingerpaints have been adapted for use in the bathtub as soap: http://www.babyant.com/bt032076.html.
