A nugget waggler is a general insult. You can scream it out the window of a moving car to yell at a passerby or another vehicle that has cut you off. You can also call your friend a nugget waggler if they are getting you angry. Generally, it is the best insult there is and can be used in many contexts.
Hey, you nugget waggler, get the hell out of my garden!
God, Christy was being such a nugget waggler last night when she stole my scarf!