Tranquil PC launches a stylish passive case for both version of the NUC (Thunderbolt D33217CK and Gigabit Ethernet D33217GKE). This 110 x 164 x 47 mm chassis is made of aerospace grade aluminium, and acts as a giant heatsink. The most awesome is without a doubt its efficiency : 5 to 15 °C cooler than the fan cooled NUC.
Quite impressive, but roughly 100 EUR.