PimpRig posted a review up on an interesting type of thermal transfer compound called Liquid Metal.

I was shocked when I pulled the cap off the syringe and saw that the needle was still there. I had no idea how the thermal interface material could get through an opening that small until I pressed the plunger slightly over the CPU. A drop of the material came out with no problem and sat there like a ball on the CPU. It was at that point that I got a little nervous since it looks just like Mercury. But then I had to think, "What company, whether in their right mind or not, would sell Mercury on eBay?"

Coollaboratory Liquid Metal - Thermal Interface Material Review