While not playing java this weekend,ive been playing with dead meeces from old PCs.Because as you may be aware a pc mouse makes a very good rotating shaft encoder.If you look inside a pc mouse you will see two optical encoders in contact with the rubber ball which rotate as you move the mouse.The mouse sends a serial bit stream back to your pc telling it how much the wheels have rotated since the last reading at a rate of upto 500 times per second then your cursor gets moved on your display normally.,ut if you arrange your rotating shaft so that it turns one of the wheels and you can connect your controller to the serial lead and all the hard work is done for you.There are two serial protocols in use depending on wether you have a two or three button variety of mouse,but they are both pretty simple to decode.I think its a good use for a dead mouse.