Thermoelectric cooling describes a way to move heat from one side of a thin, flat thermocouple device to the other. Compact, solid-state construction has made this ideal for portable devices such as plug-in beverage coolers, which have been available to consumers for many years. Moderate efficiency has even allowed these to be put to use in specialized home cooling products. However, one place these haven't seen much penetration is in CPU cooling.
Thermoelectric Coolers move heat from one surface to another, though not as efficiently as illustrated.
The reason for market resistance is simple: "below ambient" cooling solutions suffer condensation around the cold components, which can short out electronics. This is the same problem already familiar in compressor-driven phase-change coolers such as Asetek's Vapochill systems, which typically require the cooled area around a CPU to be filled with a sealant to prevent air contact. Enthusiasts have occasionally built water-cooled systems with a TEC wedged between the water block and CPU using similar sealing methods. "Cold water" coolers that have emerged in the same enthusiast circles require further insolated water lines. Any of these messy installations exceeds what the typical builder will tolerate in an "off-the-shelf" product.
Macstek Technology came up with a simpler solution to eliminate condensation problems. Developed for its marketing partner Vigor Gaming, the Monsoon II doesn't try to go "below ambient" but instead maintains a temperature roughly five degrees Celsius above surrounding air through electronic controls. While this certainly won't get anyone their "super cooled" overclocking results, it's marketed as a compact alternative to mid-sized water coolers.