Come across these sort of sites before (pay to advertise), thought I might as well list them.
Million Dollar Homepage - 1million pixels, a dollar each. Every single one has been bought, therefore owner has made $1m for a very simple idea.
Add a brick - Unlimited amount, but doesn't really have any potential as there seem to be no special bricks being added (e.g. doors, windows etc). Also, why did "CJ" pay $250 and put up that rubbish banner linking to his page on a free site hosting service?
Gratis Million - An earlier Million Dollar Homepage, but isn't in English so is losing UK and USA customers, probably the biggest source of buyers.
En Million - An earlier Gratis Million, has hardly any customers, why don't they put it in English too!
Pixel Lotto - Seemed a bit complicated, apparently you can win the $1m raised, not sure how that would work though. It's from the same people that made Million Dollar Homepage, and is in English, getting a lot more buyers than the non-english ones, starting to see a pattern.
Zero Dollar Homepage - You can't buy any!
Million Masterpiece - My favourite, because all money raised goes to charity! Click the question mark in the top right hand of the picture and select one of the pictures, some are very funny, all are random. Also, they are all individual people's drawings, not big companies buying all the space.
Pixel Ads For All - Quite a nice one as it offers a free 100x100 pixel space to advertise when your pixel is moused over. This allows companies to put up a large advert, without using up any of the space.
Million Pixel Click - Seem very friendly, appear to be giving away half the space for free if you link to them, so placed a link on the toolbar. Will update when I find out if I was accepted or not!
Here is what I sent by the way:
Million Dollars Pixel - Animations are allowed, which is a big improvement, I especially like the Mad Smiley and the apparently Swimming Tree! They seem to be very unpopular though, only 7 visitors today, maybe it's because of their messy layout?
Billion Dots - Similar to all the others, except on the moon! Also, good to see my old favourite YetiSports advertising on there!
Make Me Mortgage Free - Basically, you are paying this guy's mortgage for him! You choose where you want to buy, e.g bathroom, bedroom etc. Makes a nice change!