I've made scripts that cause effects to pulse on certain tokens or certain parts of the environment to represent things like burning, lighting, and flying. Unfortunately, I found these to be almost unusable as the effects will be viewable in areas that should be blocked by lighting barriers and even appear when the token creating the effect is on the GM Layer! Effects like fire, smoke, and blood-spray should not be viewable if they are hidden behind lighting barriers or if they're appearing on the GM layer.