BitcoinPixels.com is purely for representing anything bitcoin related. Do you have a website which accepts bitcoin as a valid payment? A website which talks about/mentions bitcoin? Then you can buy pixels which provide a link back straight to the page of your choice. You could have your logo representing your website, alongside other bitcoin related websites. People will come here to browse what bitcoin has to offer.
only 0.03BTC per 10x10 block, that's 1BTC for 3000 pixels space and you get that advertisement for 1 year. Free advertising if you offer an affiliate program