The Million Dollar Homepage contains only a single image. That image is a giant, ugly, expensive advertisement. And that giant, ugly advertisement made some college kid in the UK one MILLION dollars.
The idea is simple: Create a 1,000,000 pixel image, and sell those pixels off for a dollar each (in blocks of 100). People are free to use those pixels to link to advertise whatever they want (online casinos and scams mostly, it seems). Every single pixel sold out, and Alex Tew of Wilshire England made a cool milli. How could he make so much off of something so dumb? Because he thought of it first