Instructions
Reach behind the PS3 and flick the power switch to the off position.
Place your finger over the eject disc sensor on the front of your PS3.
Turn the power switch on the back of your PS3 on with your finger still covering the eject sensor.
Wait for the PS3's fan system to kick in. When you hear a whirring sound from your console, it is an indication that the fan cycle has started.
Keep tapping the eject sensor with your finger and eventually the PS3 will eject the disc.