Google AdSense can support a site?

Tim Bray investigates the monetary implications of his experiment with Google’s AdSense program:

Which is nothing that you’re going to retire on, but it would certainly cover the site’s costs and buy a couple of beers. And if you could drive the hits up, you could actually generate noticeable income.

Tim has a fairly busy site, but it looks like he could get several hundred a month from Google’s AdSense. At present, Google’s general policy is to not allow blogs, so I couldn’t sign up. I don’t do this blog for cash anyhow. But it’s interesting to think of what some sites that are trying to make a profit could do with this.