Hardware Secrets tested more thermal pastes, you can read the results over here.
We added five new thermal compounds to our previous roundup, for a total of 40 different thermal compounds from major brands. We also tried another "alternative" compound: chocolate.
Here is a snippet:
"Following up on our Thermal Compound Roundup - August 2011 review, we are adding five more thermal compounds to our roundup, for a total of 40 different models from Akasa, Antec, Arctic Cooling, Arctic Silver, Biostar, Cooler Master, Coolink, Deepcool, Dow Corning, Enermax, Evercool, Gelid, Glacialstars, Nexus, Noctua, Prolimatech, Scythe, Shi-Etsu, Spire, Rosewill, Thermalright, Thermaltake, TIM Consultants, Titan, Tuniq, Xigmatek, and Zalman. In this review, we will determine if certain products are superior to others. We will also try another "alternative" thermal compound to see if it works."