Another useful and simple mod from Merlin's Software:
Translate topic urls that point to topics on your own forum, into their proper topic title.
It automatically changes this:
The topic title
which makes references to topics so much more legible.
It is a very easy mod, just two small changes in posting.php and one new function in includes/functions_post.php.
EDIT: It translates all viewtopic urls now, both to topics and to posts, also with more variables in the url.