I got an ad from Innov8tiveDesigns touting their electric props for multirotors.  They are called GemFam and they come in normal and reverse rotation.  Anybody try these yet?  What do you think?  Here is what the description says for the 11x4R prop:

GemFan Wood 11x4R Multirotor Prop
[GF-11x4R-W] $7.49


GemFan produces some of the finest props for Multirotor use, and the new Wood Series props offers a wide selection a sizes that are specifically for use in hovering flight applications. All of the various size wood Multirotor props are available in both normal and reverse rotation. The blades on these props feature an eliptical blade shape that produces a more uniform thrust distribution across the entire blade surface for maximum lift and thrust efficiency.

The 11x4R props are reverse pitched, have a 6mm diameter center hole, and have an average weight of 19 grams or 0.67 ounces. The weight of wood props can vary due to slight variations in the density of the wood, so the actual weight can vary somewhat.
 

http://www.innov8tivedesigns.com/index.php?cPath=46_148

The larger sizes come in a 4.5 pitch.  I'll have to try one out to see what RPM (pitch) they really run at.