Please mention companies I haven't thought of.
AngelEye
Aquacomputer
Asetek
CoolerMaster
Corsair
DangerDen
Eheim (Aquarium pumps)
Evercool
Gemini
Glacial (Mitron \ Noise Isolator)
Global WIN
Hydor (Aquarium pumps)
Innovatek
Kingwin
Koolance
Little River Waterblocks
NextCool
PolarFlo
Silverprop
Swiftech
Thermochill
Thermaltake
Titan
Zalman