g1smd - 11:33 am on Feb 15, 2010 (gmt 0)
If you use URL rewriting, there's a speedup to be gained by optimising the regex patterns in the rules, adjusting the order of the conditions within a rule, and maybe even adjusting the order of the rules. If the rule conditions use 'file exists' and/or 'directory exists' checks, there is a huge gain to be had by coding these correctly (Hint: the standard .htaccess rules supplied with Wordpress, Joomla, et al. are about as inefficient as you could ever get). See WebmasterWorld's Apache forum for more detailed discussions of these topics.