Environment mapping effect for map surfaces? Easy code to do, just the glquake sky surface poly warpping effect, but without the scroll and uses an ordinary texture image. Kurok has this effect for glass and metal surfaces if you want to see what I'm talking about.
No idea how to do the effect in software rendering though, but I imagine it's quite possible. Half-Life did the effect in software rendering for certain models, like the revolver, black parts of the HEV suit and the black op girls.
Would be neat for Quake models too
