Here in 'Murica, this combo (roofing work + beer + friends/audience) is like a signal from God that you need to perform some crazy death-defying stunt. I'd vote for something that involves spraying lit gasoline, or perhaps a you can work in a pipe bomb somehow. At least try using the garden hose to get somebody to 'beer-bong' a gallon or so from up on the roof
- and we need pictures, don't forget.