This is a great chart showing the different energy transfers that occur in the universe. From the smallest wiggle of a photon to all the energy expended since ever in the whole Universe...
http://www.circlon-theory.com/HTML/joules.html
Some notable items on the chart:
- 2.6845 * 106 - One horsepower per hour
- 1013 - Titanic fall to the bottom
- 1048 - yearly output of the Milky Way