PSP Push-Activated Shoulder Button Lighting
Everett has put together an article explaining how to make those conveniently clear shoulder buttons on your PSP light up when they're pressed. In the article he uses surface mount LEDs from an old cell phone and limit switches from a CD-ROM but these are things you can most likely find at your local electronic supply story or online. Be aware that this does involve soldering and
will void your PSP's warranty. Everett gives very detailed instructions on how to place the LEDs and run the wires as to no affect the movement of the shoulder buttons or any of the other buttons. Below is a link to the how-to and an image of his finished product.
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