
This guy decided to sell some ad space on a web site. You buy a pixel for a dollar. It stays on his site for a minimum of 5 years. The only requirement is that you buy 100 pixels - a mere $100.00 investment.
How big is 100 pixels? Below is a screen shot of an ad 100 pixels (10 pixels tall by 10 pixels wide). I erased all the other ads around it so you can see it all alone. Look close, it's up in the left corner. I made a little red arrow pointing up to it.

From his FAQ:
Are you genuine/is this a joke?
I am completely genuine and although this site might be funny in various ways, it is not a joke! I really am selling pixels for $1 each, because I don't want a monstrous debt when I graduate. I am pixel hustler and proud!Some people have even asked if I am actually 21 and going to University. Fair question I guess. The answer is of course yes, as this photo of me and my uni acceptance form should prove to any doubters: