Pareto's Law in real life

Pareto's Law of Economics roughly states that 85% of the world's wealth is owned by 15% of the population. It is often generalized and referred to as the 80:20 rule.

It has MANY applications:
In manufacturing and production, 80% of the production is accounted for by 20% of the products.

80% of the world's polution is caused by 20% of the population

80% of my time in my house is spent in 20% of the space (the kitchen and bedroom!)

80% of a group project is done by 20% of the group's members.

N used it once in a class presentation and got harassed by an unsuspecting international student who was later "destroyed" by the rest of the class.

So why blog about it, I came up with another yesterday that is a bit depressing. Teaching this one class accounts for 80% of my work time and only 20% of my income.

Feel free to add to the list.