This can be useful for instance to skip confirmation pages after posting messages on message boards, skipping ad pages that appear before you can view content on certain sites, redirecting from http to https on sites where you always want the https version, redirecting from one hostname to another for proxy servers, or just anywhere where it takes you two or more clicks to get to what you want.
The extension supports both wildcards and regular expressions in patterns. Regular expressions support capturing parantheses so you could define the pattern: http://foo.com/bar.php\?id=(\d+) and define the redirect as http://bar.com/baz.php?id=$1. In that case http://foo.com/bar.php?id=1234 would automatically redirect to http://bar.com/baz.php?id=1234. As of version 1.5 wildcards can also use $1,$2 in the redirect urls, $1 is the contents of the first star match, $2 of the second and so on.
Bugs, feature requests and comments, please send to redirector ( at ) einaregilsson.com