Man do I feel your pain. Good thing I was working and made enough money to buy a PS3 Slim. I hope the Slims don't get the YLOD because I am not looking forward to spend more money on a console that doesn't last as long as its past systems.
This is what I did when it happened to 2 of my PS3's.
1. Buy Thermal Paste/ Thermal Compound (At least 2 tubes)
2. Open your PS3
3. Get a hair dryer and heat up the Motherboard
4. Apply the Thermal Compound to the 2 square, silver heat pads
5. Close the PS3
6. Use the hair dryer to over heat your PS3 by heating up the vents. Don't keep it too close to the vents or you'll melt the plastic.
7. Press the power button repeatedly while overheating the PS3. The system won't turn on yet, but wait till you press the power button and here 3 beeps without the YLOD appearing.
8. When that happens, wrap it in a towel.
9. Wait for it to cool off COMPLETELY
10. Turn it on. It should work, however, it will only last a week tops, so play it for a bit, back up your data and sync your trophies, then sell it. (Preferably a pawn shop. Guaranteed 100 dollars.)