Arctic Silver Ceramique
When I first took a look at this TIM I thought to myself "Oh no...SILICONE!" But even though it looks like a silicone based compound, that is where the similarity ends. The Ceramique compound is made from aluminum oxide, boron nitride and zinc oxide sub-micron particles. Again, this is some pretty fancy talk, but it all boils down to a non-silicone based suspension containing very small pieces of these thermally conductive materials. The idea is to have these elements get the heat away from the core as rapidly as possible so that the heatsink can do its job more efficiently.
The texture of the compound is smooth and almost sticky in a sense. While it does manage to clean up nicely with a bit of Isopropyl Alcohol, it tends to affix itself to whatever you're applying it to. It also contains no silicone so will maintain its thermal transfer properties over extended periods of time. Applying it to a processor core showed it to be the smoothest of the lot tested today.
Another benefit of this compound is that it totally non-conductive, even when accidentally placed on or near the processor bridges. This eliminates the slight chance for mishap that was possible with the silver based compounds.
Also of note is the requisite burn-in time. Both of the silver based silver products require a three day burn-in, but the Ceramique requires only a 12 hour burn-in. This makes it much faster between application and maximum thermal transfer capabilities.
Arctic Silver Ceramique comes in a bit smaller 2.7 gram syringe, but the smooth texture will still allow for roughly the same amount of applications. Cost is US$4.99, which works out to roughly $1.85/gram, so it is even a bit cheaper than the others.