Yes, it's been done before by Alex Tew on Milliondollarhomepage.com. Buy blocks of pixels on a page and post an image. The difference here is that it's free.
You can get a
10 by 10
20 by 20 pixel block free on Billion Dollar Exit. This pixel site is focused on helping startups gain visibility and ultimately, get funding from venture capitalists and angel investors. Right now, I could name dozens of sites that are attempting to gain mindshare in the social-bookmarking/Web 2.0/tagging market. They're all buried underneath the behemoths of del.icio.us/digg/Technorati. That's unfortunate since many of them have interesting takes on collaborative filtering and social networking.
Billion Dollar Exit is set to be the single point of contact between VCs and emerging companies, and your company could be the next to get viral.
Get your Billion Dollar Exit