In the code shown below, the h2 tag is not visible in IE6 or IE7. It shows up normally in the other browsers that I've checked.
This is just 28 lines of HTML, and it validates. There are only four styles. If you remove any of the styles, the h2 will show up. I think this is related to the adjacent float bug. I'd appreciate any comments/suggestions. Since, as you can see, I've tracked the problem down, I know how to fix it. What I'd really like is to be able to learn from it.