My 40GB died with a YLoD just after the 1 year warranty expired. What was annoying about that is that I had only been using it as a blu ray player (deal on PS3 made it the best/cheapest BD player at the time), and it died right after I decided I should finally pick up a game for it (mainly use Xbox). Thankfully, I was able to use the credit card double your warranty claim, and replaced it with a 120GB slim. It is still working.
My original Xbox360 Elite, that I use the heck out of, is still running great with no repairs.