I propose a design whereby the fan is enclosed between the two sets of copper heatsink blades in a radial arrangement, with heat pipes. Basically similar to the heat sink design shown at the top of this article, except for the following:
1. The two halves, each with its own set of heat pipes, are assembled similar to example above, i.e. attached by screws to the common base. Thus they enclose the fan from all sides, increasing airflow efficiency, decreasing noise, and making it impossible for any loose object or cable to block the fan blades.
2. One or both halves may be user-detachable (using high quality thermal grease if needed) to allow dis-assembly for fan replacement or cleaning.
3. Copper fins are curved in the direction of airflow, making them work like static turbine blades and cutting down noise.
4. Copper fins are trimmed on the outside to form a rounded-corner cube rather than a cylinder. This optimizes the cooling area in a given space inside the case.
-- Alex K. NY