What you will need:
1 a old ps/2 or sub keyboard
2 some low voltage relays
3 some wire
1 a nice box/case
2 dip socket
screwdriver which fits in the screws in your keyboard
Step 1: Opening the keybord
open your keybord.
throw away the white plastic sheets but keep the sercet bord
Step 2: Using the keybord cercit
Step 3: Wireing the relay
use tape on connections and-after you have tested it, on all exposed conductive material and to secure the relay.
Step 4: Prepareing your box [optinal]
in the other to holes, put the led in one and thred the wires through the other.
then screwthe box together again.
Step 5: Testing
then make the cercit in the picture. now press the buttons you assined on the computer. if the led lights up woo! if not, check led being the right way round, battreys having power, and that all conections are conectid correctley and that nothing is touching that shoudent be.