I was looking for places to submit the BBclone web counter and I came across this:

This week - Alexa top PHP sites by user reach


No prizes for who guesses who is in the top 3, but what is also interesting is that the script is available for your sites and it doesn't have to have each site showing up as a link. Top 10 PHP Sites script available for download It is available out of the box for the CMS Geeklog and with minor adjustments will work on any PHP page.

Using this code, it will be possible to choose any Alexa sites to show as rankings. One's for webmaster forums, web hosts etc could be made just as successfully. One note though, the Alexa rankings only really have any kind of accuracy for the top 100,000 and the higher up you go the more accurate it is.