Jayson Anders writes: Research has been done demonstrating a far superior type of thermal compound using diamond. Silver has a respectable thermal conductivity at: 429W/m K. Diamond on the other hand has a thermal conductivity of 900-2320 W/m K. So worst case scenario we double performance, and best case is roughly a 5x multiplier. The folks over at Recommendedspec.com have put together a article showing you how to make your own!
"The fundamental principle of science, the definition almost, is this: the
sole test of the validity of any idea is experiment."
-- Richard P. Feynman