This video shows a Photoshop action that aligns one layer to another regardless of their position and size. It is particularly useful when you have to distribute one layer to multiple files (for instance, lets say you have to include an identical set of teeth in multiple character textures).

Polycount forums thread:
polycount.com/forum/showthread.php?t=75466

Loading more stuff…

Hmm…it looks like things are taking a while to load. Try again?

Loading videos…