For the 'Role With It' production of Alice in Wonderland in December 2013, we produced a back projected, animated Cheshire Cat (rolewithit.co.uk).
We came up with a back projected animation, utilising actor Lisa Allen (northofwatford.com/Lisa-Allen) speaking the lines. Her mouth was then rotoscoped and warped into a smile, and complimented by animated eyes and whiskers to create a disembodied cat's face.
Here's a breakdown video to show how we did it.
Shot on Nikon D5200. Built in AfterEffects.