Is there really such a thing as a muffin scoop?
Cookie Scoop, Muffin Scoop, Disher.... They come in all sizes and are useful for a whole lot (except I don't like them for ice cream). See here:
http://www.kitchenconservatory.com/Dishers-and-Scoops-C461.aspx

Alton brown frequently uses these scoops for all sorts of things on "Good Eats", including his episode "The Muffin Method Man" where he uses a #20 scoop:
http://www.goodeatsfanpage.com/Season7/Muffin/MuffinTrans.htm

Another example of using scoops for muffins.
http://www.goodlifeeats.com/2010/10/kitchen-tip-trick-for-filling-muffin-tins.html