SnowfallCursor 

This is an addon that improves the visibility of the mouse cursor, making it easier to find in a chaotic environment with lots of spell effects and whatnot. The addon places a star at the cursor, with size proportional to the cursor speed.

There is no configuration whatsoever. It's just the way I like it, already! This addon is tiny, though, so if you're handy with editing addons, you could very easily modify size, texture, and so forth.