Ok, got one more with an optional parameter in it.
http://www.imfdb.org/index.php/Template:Duplicate
This is for duplicate pages and images. To use it, enter it as {{Duplicate|}} with a link to the page after the |, as you'd format an internal link. For example, if it were a duplicate of the page
http://www.imfdb.org/index.php/Full_Metal_Jacket, you'd enter that as
{{Duplicate|Full Metal Jacket}}
If you're linking to an image, change "image:" in the link to "media:" so it won't be displayed in the template. This is to speed things up for admins, so they don't have to
find the page it's a duplicate of. It puts pages it's on into the same delete category as the other one.