Here is search logs of 650,000 AOL users. It's very interesting to view search history of particular person and analyze his personality. Let's do it together! Read more about AOL search database scandal or view research papers on web searching.
PECL
A full-featured profiler/debugger that is loaded as a zend_extension. It aims to be an analog of C's gprof or Perl's Devel::DProf. Offered from PHP.net [Open source, GPL]