Common vinyl Spackle can also be used for a filler for very small applications and in areas not prone to constant wear. It is not durable and will always remain water soluble, so when the top surface of paint is removed, either by wear or abuse, this filler will not remain on the surface if exposed to moisture or wear.
A stiff brush and a palette knife can be used to apply the spackle. The preferred type goes on pink and turns white when completely dry. It also does not mold in the container. It can be thinned with water.