Specialty paints are used for several purposes including glazing paints, outdoor paints and stains for fences and patios. There are also products such as ceramic paints and specialist heat proof paints that can be used for painting radiators. So basically specialist paints will be used anywhere that regular gloss or emulsion would not be suitable.
A very popular specialty paint are the child proof paints that are designed to be wipe clean paint once dried, so if your child draws or wipes dirty hands on the wall you can simply wipe it clean. This kind of paint can come in a large variety of colours and even though it has the benefit of being wipe clean it doesn't look any different to normal paint besides the fact it has a more silky feel to it.
You should ensure that you're using the right kind of paint for the surface you're painting, if not then the finish will more than likely be impaired. If for example you tried to paint a radiator with normal gloss then the paint could either start to flake off or could be scraped off easily.
With some specialist paints there are certain tools you should use to apply the paint to get the best finish you possibly can. For this reason manufacturers have developed a range of special rollers, brushes and textured materials for applying specialist paints.
Specialty paints can add character and depth to a room, turning fixtures that are not commonly painted into veritable design features.