i saw such timer, in youtube, so i asked the guy how he made it, he said:
"just a regular cheap timer
2 wires
and a 2 way switch
the best switch is what they use on arcades
i just got lucky in studying the switch i think its easy
in the timer you need to know the start/stop button
and take off put a wire on any positive or negative
and the other wire is for negative or whatever
put the ends of the wire to the switch and with just trial and error you may find the right spot on the switch "
so, i really didn't made that timer, i just made a timer from old keyboard, and put the circut in a project box, and put 2 metal plates, for my hands to lay down on
watch his video:
http://www.youtube.com/watch?v=b5g6WsnxjQ4