For the price of the Iraq War, we could've bought a Ohio State - Michigan football ticket every year until the Sun becomes a red giant and engulfs the Earth.
The Sun is currently in its main sequence. In 5 billion years, it will burn all the hydrogen in its core and helium fusion will make it a red giant. It will grow to 200 times its current size and engulf the earth.
At this writing, tickets to the Ohio State - Michigan football game, perhaps the biggest college football rivalry game in America, start at $400 each. For this price, buying tickets for the OSU-Michigan game until the sun becomes a red giant would cost $2 trillion dollars, which is less than Joseph Stiglitz and Linda Bilmes' estimate of $3 trillion for the cost of the Iraq War.