I got the dreaded Red Ring of Light on my XBOX 360. The error code was 0102 and thanks to Google I found tons of postings with successful fixes. It requires about $8 worth of screws and washers to replace the poorly designed X-Clamps that clamp the heatsinks to the GPU and CPU. These clamps cause the motherboard to bow and slowly with time and heat the soldering becomes weakened.
This video shows how to remove the X-Clamps. You just need to pry off two of the four legs of the X-Clamp and you can slide it right off.
Just grab a pair of needle-nose pliers and watch the video.
The tutorial and parts list by LAWDAWG0931 that I used can be found here: