HELP/PAINT: Can it be used as an anti-graffiti paint?

Absolutely. WriteyBoard 1-Part Dry Erase Paint makes an excellent anti-graffiti paint. Note: the more porous the surface, the more paint is needed. If the surface has been painted or has a sealant, it will probably cover in just one coat; if the surface is like untreated concrete or brick, it make take additional coats based on its surface porosity.