My wife teaches the 8th grade and does a unit on Shakespeare. This topic comes up every year. It is time to add some depth to your put downs.
Here is a website that has 50 of them in context:
Here is a better version of the generator as a PDF:
And here is an actual generator - Thou surly spur-galled pumpion!
http://www.pangloss.com/seidel/Shaker/index.html?
Enjoy.