Joykey is a simple solution to get a functional joystick on your keyboard.
Just need attach a little square piece of adhesive Velcro on the base of the model.
Note that this system press the key "5" key all the time during the use, but this key normally is not atended on the clasics games.
Remember: There is only one way of correct use. You should put on the pin that have a little triangle, oriented over the key "8" of the keypad (see the picture)
There is some more information extra here (in spanish) http://zonadepruebas.com/viewtopic.php?f=26&t=6158&p=56043#p56043