Cheapest bluetooth chip? (Wanting to make a bluetooth controller)

Ok, so what I'd basicly like to do is make a simple controller for use with my android phone for emulators, and other games that may support a bluetooth keyboard, or somehow simulated to android.

So, I ask, what is the cheapest bluetooth chip that can be used with arduino with out a massive effort to get it working? I'd like to make a small controller that attaches to the side of my phone to add in a physical gaming controller. Goals would be at least a d-pad and 4 buttons. (probably a few more buttons, but that's the minimum I'd want. Any help with ideas of the best way to pull it off would be nice. Right now all I can really think to do is have a program run in the background reading a bluetooth serial connection.

(Please note, I know that there are some bluetooth controllers out there that work, but I'd still like to make my own, as most are over priced and way to bulky for me)

You have these kind of chips:

http://www.dealextreme.com/p/wireless-bluetooth-rs232-ttl-transceiver-module-80711

You find them also on ebay. The thing is though these modules have firmware which enables certain functions. The best firmware I beleave is the HC05 firmware a link can be found on the dealextreme forum questions below the product post.

Itead has one as well (they have the HC06 and HC05) and they provide the eagle footprint.
http://iteadstudio.com/store/index.php?main_page=product_info&cPath=7&products_id=157
http://iteadstudio.com/store/index.php?main_page=product_info&cPath=7&products_id=206

In the thread of Westfw on the optiboot bug fix someone has made a change so bluetooth modules without auto reset (most of the modules firmware don't have hand shake lines enabled) can be used for downloading new code to the arduino.

Thanks for the tip wortelsoft! I just ordered one of these from DX. Can't wait to play with it.