Edit your HTML files with a one-line perl program

" If you maintain a number of HTML documents on a Unix WWW server, you may sometimes want to make the same change to a number of files. Doing so by hand in a text editor can be tedious, but one time-saving option is to edit your files in place with a perl "one-liner". Best of all, you don't have to be a perl expert to do it."

http://www.rice.edu/web/perl-edit.html