Snake Method
With the Snake Method you are able to keep a consistent low temperature for a long period of time.
Make a 2x2 stack of unlit briquettes on the outer edge of your barbecue. And place a few lit briquettes at the beginning/head of the snake.
You can place a few smoking chips or small chunks along the first few inches of the snake to enhance the flavour.
The Snake Method can run for about 12 - 15 hours depending on the length of your snake.