Forum Moderators: open
RewriteEngine On
RewriteCond %{REQUEST_FILENAME}!-f
RewriteCond %{REQUEST_FILENAME}!-d
RewriteRule ^(.*)$ /search.php [L]
This says if the request is not a file (-f), and it is not a directory (-d), direct it to search.php. In search.php, you will have to add some programming that takes the referrer string and correctly converts /search/keywords to query words=keywords.
(Edit: this board software removed some spaces, there needs to be a space before the exclamation --->!)