rolf wroteWater cooling is exactly what your car engine has, water is run through it and there is a radiator in front that dissipates heat. Water cooling is efficient and very silent, but expensive and a bit more complicated to install, but above all a bit risky (because of the water in it) and might need maintenance and fixing from time to time. That is why computers are fitted with air cooling by default.
Spot on; as an engineer I get to see both forms of cooling: fans for motors and water cooling systems for IPL crystals. The usage of fans is less risky (no water involved = no chance for leaks and fear of damaging electric systems) and doesn't require a lot of maintenance (unlike water cooling systems where you have to open the tubes every 3 months due to the calcification that will occur thanks to our lovely water supplied by the government, and the water must be changed every 6 months... even filtered water: we use distilled water and have to change it twice a year). However, they are noisy, but some systems surround the motor and fan with anti-static foam:
which by the way doesn't heat up easily.
The simple advantage of water cooling systems is that they can reach a cooling temperature of 0 degree Celsius (yep, zilch) and the object being cooled becomes ice-cold. I don't know much about existing water cooling systems for computers, but I'm very skeptical that they can reach very low temperatures => useless to buy and install.
Go for the fans, and use a sliencer foam.
@Tarek: Peltier junctions cool on one side and heat on the other (Seeback effect). Not recommended.
