Andrew Wulf passed along a note about an ajax-based PHP documentation site aimed at making it simple to get at the PHP manual from a single page interface.
I wrote this little app for my own needs initially, as PHP is such a big monster that it was hard to find the right documentation, or discover which of the N similar packages I should use. When I moved servers I fixed up the app enough and decided to release it to the world. It's pretty handy as is, but there are still several things I need to add, particularly paging through the documentation, and supporting bookmarks.
The site, phpdox.net, supports two kinds of searches - one through an index of page titles and another through the hierarchical names of the documentation's filenames.