Copper mineral water:
90 ppm (parts per mil.)
Cost about USD$50 per gallon
Suitable for human consumption. Essentially nothing but pure water as far as PC cooling is concerned.
What you were looking for is called nanofluid, among other things. There is some info here:
nanofluid
From the article:
Quote:
|
....the heat-transfer capability of ethylene glycol grew by 40 percent when only a 0.3 volume-percent of 10-nanometer-diameter spheres of copper were suspended in it.
|
Hope this helps.