You could do this: Work with mod_rewrite to change requests from

/some/static/page.html

to

/htmlinjector.php?url=/some/static/page.html

then use PHP (or whatever you find appropriate) to do the file-manipulation. Add an output cache to improve performance.

You could do this: Work with mod_rewrite to change requests from

/some/static/page.html

to

/htmlinjector.php?url=/some/static/page.html

then use PHP (or whatever you find appropriate) to do the file-manipulation. Add an output cache to improve performance.

As an alternative, Apache Handlers sound helpful:

Modifying static content using a CGI script

The following directives will cause requests for files with the html extension to trigger the launch of the footer.pl CGI script.

Action add-footer /cgi-bin/footer.pl
AddHandler add-footer .html

Then the CGI script is responsible for sending the originally requested document (pointed to by the PATH_TRANSLATED environment variable) and making whatever modifications or additions are desired.

This is more or less what the mod_rewrite approach would do, only with less hackery.