In acrylic there's also the Montana-Cans line, similar to Spray.Bike, but with more ("can" be confusing) options. This stuff was either developed for or adapted by the graffiti "industry". I haven't tried any of it, but find it interesting because the basic idea is no or little drip tendency, and working much closer to the object typically (though distance recommended varies depending on the different effects/types). Acrylic tends to be not as glossy as spray enamels, I think, and maybe softer too, but there are clear coats, glitters and so on. It's pretty amazing what one can get in a can.