Potential Project: Interchangeable Extruder

Hello fellow printers
I have an idea that I would really like to throw out there. Has anyone thought about how to switch out extruders? EX: I want to print out something in Blue filament with a .2mm nozzle, and my next print I want to print in white with a .6mm nozzle. Is there a way to just switch extruders that are loaded to that filament and nozzle ?