Used the recipe in the Good Eats episode:
A Grind is a Terrible Thing to Waste.
I processed Chuck and Sirloin. It was my first attempt and next time will have to grind it a little longer because my food processor sucks, but either way they were the best burgers I've ever had.
Next time I do this recipe; I'm going to fire up the grill.
Just thought I'd share and hope you enjoy.