Global Variables to Determine Color

I had a project where I needed to set specific objects throughout all my comps to global color values.

1. Create a comp called globalVars and add a null layer named globalVars
2. In this layer add a Color expression control and set to desired color. Name it Color1.
3. In another comp select a layer and add a Effect>Generate>Fill effect
4. Set the filled layer to this expression: comp("globalVars").layer("globalVars").effect("Color1")("Color")