Beer. Undoubtedly beer. There's this odd pattern in history...people start making beer, then huge monuments start appearing. Stonehenge, Egypt, South America, Greece. When they were building the Coliseum they were way behind. You know how they got caught up? The workers were offered an extra portion of beer as a bonus.
That still works today. If you have to build a garage or put a roof on or move all of your belongings from one place to another you call up some guys and say, "Beer," they will come and work all day for free.