A publisher at WebmasterWorld couldn’t believe his eyes when he saw an AdSense ad unit with extremely small fonts.

The fonts were so tiny, it was hard to read, let alone click on.

Here is a screen shot he uploaded:

At first you think this may be a bug with the user’s browser, but the publisher is a old timer, being with WebmasterWorld since 2004. He wrote:

I wouldn’t be surprised if Google did test it but I doubt we will ever see such an ad unit approved for the public.

Forum discussion at WebmasterWorld.