Help with a Switch

Hello, i was wondering if anybody could help me but i have a problem. What i'm wondering is does anybody know of a momentary switch that could be programmed to stay pressed for a short time (around 0.75s) and then simply stop? Any help would be appreciated.
oh and reason for this i've had an idea for my xbox 360 controller. Thanks, tom.

Hi.

That will be a timer circuit and a relay.

Thanks for the reply. Do you have any idea how i can integrate this into an xbox 360 controller? What i'm looking to do is to add a momentary switch to the controller motherboard to the "B" button and then get a current from soldering the other part of the cable to the LED. How could i add a timer circuit relay to the circuit so when i press the momentary switch the B button will remain pressed for 0.75 seconds?