script (featured in April)
AutoReviewComments - Pro-forma comments for SE
One of the first scripts I ever installed, and it has been a major productivity saver ever since. When moderating sites (as a regular user as well as a moderator), some situations come up over and over again and can benefit from a standard comment from this script. You can even add your own standard ones or modify the existing templates.
It's a pity that it's no longer maintained (various users, including me, have their own personal forks now). But even in its current form it's worth giving a try.