Here's some research in to alternative keyboard layouts which are (arguably) even more efficient than Dvorak and Colemak. [Also included is an application for optimizing your own keyboard layout based on criteria that are important to you (such as minimizing the use of the little fingers, weighting one hand more than another, etc..)]:

http://mkweb.bcgsc.ca/carpalx

The most efficient keyboard layouts are described here:

http://mkweb.bcgsc.ca/carpalx/?full_optimization