I use this one the most, but I am not 100% happy with it. I did not pay anywhere near that though..
M-Edge | Products | Incline Case
I also bought this one: The keyboard works well, but I do not like the texture of the case, and it does make it pretty bulky. I do NOT like how it latches closed, what a PITA.
http://www.amazon.com/gp/product/B008QJXPAY/ref=oh_details_o01_s00_i00
I am considering one of the Treegloo cases, but don't know for sure that I want to drop the hammer @ $70 after shipping