Visiting Venus to hot? Heres the Answer...

[link to www.grc.nasa.gov]
NASA proposes using a Stirling cooler (essentially a Stirling engine in reverse) to keep a probe cool on the surface of Venus, which has had a tendency to melt or smash previous probes. The cooler would maintain a 25cm sphere within the probe at 200°C -- 100°C above the boiling point of water but sufficiently cool for a high-temperature microcontroller to operate. The waste heat radiators on the exterior of the sphere would reach the temperature of 500°C, 40°C above the the normal Venusian surface temperature.
[link to space.newscientist.com]