I hate just giving an example without explaining how or why it works, so instead of giving you shader code I'll explain the concept. Making a texture shiny is achieved by overlaying a second, transparent texture that then moves around (the reflections). To then prevent certain parts from being shiny, you could overlay another texture with transparent parts on it. The non-transparent parts would thus hide the shininess. The exact shader varies depending on whether you need a lightmap etc. You're thinking of an on-character HUD akin to Dead Space? Having procedural shaders is not unheard of: Jedi Knight Galaxies has weapons with Ammo Counters and Hydroball has the in-map scoreboards, but this requires code modifications which make it pretty tricky if you're not into coding. I would assume this requires coding as well, but I don't know for sure.
