Three Red Lights Of Death can be fixed using a hot air gun and some foil.
Remove the GPU heatsink (the big flat one).
Insulate the connectors (and most of the board except the areas surrounding the RAM and GPU) with the foil, paying particular attention to the eject and pad-learn buttons as they melt easily (trust me, I know!).
Heat the board up using the gun for 2 minutes maximum. Keep the nozzle moving around, don't forget to do the underside (more RAM chips) too, but be careful not to squash those buttons at the front when you do so.
Now concentrate the heat on the chips themselves rather than the board, but still moving the nozzle around. Once again, 2 minutes maximum.
Let the machine cool down, then reassemble.
This method will fix error code 0102, and maybe others (got a 0110 error to fix this week sometime).
To get the error code:-
When the three red lights are flashing, hold the pad-learn button and press eject. The lights will start to rapidly flash either all four (0), one (1), two (2) or three (3) quadrants. This is the first digit of the error code.
Keeping the pad-learn button down, press eject again, this will give the second digit.
Keeping the pad-learn button down, press eject again, this will give the third digit.
Keeping the pad-learn button down, press eject again, this will give the fourth digit.
Keeping the pad-learn button down, press eject again, this will return to the three red lights of death.