I developed a bluetooth adapter that I describe here: http://www.droidinthedark.com/fstop-...ger-bt-adapter. I have release the code that the interface uses so that anyone can build it own using an arduino and a bluetooth module like the RN-42.
Originally Posted by Mainecoonmaniac
The only problem with these is price. It turns out to be quite expensive to make only few of them. Just the cost of the PCB alone can go from 40$ a piece to 2$ depending on quantity. Hence, unless a group is formed to order them in batch, the prototype/DIY/open source approach will be the only way to go.