1 pixel by 5 pixel font
distractionware.com
distractionware.com
Edit: Well, apparently I didn't even realize it was the lyrics to Never gonna give you up. Tells you how hard to read the font is! Once you know it though, the font suddenly becomes much easier to read!
It does help you appreciate just how small we can make pixels, though. Given that we can make pixels so small, I wonder if there could be a market for B&W triple-resolution display? If I valued high-res over colour?
Hrm, it's possible to write a zoom tool that emulates the LCD sub-pixel effects. I bet that people working on such technologies already use one, otherwise they'd lose their sight squinting at their monitors.
http://www.flickr.com/photos/dafalcon/5204409225/ http://www.flickr.com/photos/dafalcon/5204413187/
Edit: Not trying to be a dick, but the site was down for me (and others, as reported by Down For Everyone...), so here's the Google cache: http://webcache.googleusercontent.com/search?q=cache:distrac...
I also made a web-based generator: http://msarnoff.org/millitextgen
After working on it, can you easily read text in your font?
The best way I've found to "read" it is to learn "c" and then guess words given the context and easier letters...