Blender should do. However, the blender might generate its own field. Putting magnets on pipes leading to your water heater or the like will affect the water. You dont really need to buy a $1000 system. Re "north pole" vs "south pole" might want to look into that. It might depend on what is desired.
http://www.decluster.com/science.htm
http://www.decluster.com/science.htm
http://www.ehow.co.uk/how_7585842_di...treatment.html
There is/was a site that showed the results of lots of mineral deposits dropping out of a household water system simply from placing magnets against the pipes. If I recall correctly, the north poles faced in toward the water. However, if i recall correctly, it was necessary that the water be allowed to run for a while to allow the mineral deposits to flush out--the water had a color apparently for as long as it took the mineral deposits to flush out.
http://www.ener-tec.com/OurProductLi...4/Default.aspx
The lower the surface tension, the more 'fluid' and the less 'clumpy' the water is. Naysayers that I've come across like to imagine water to always be pure H2O when obviously the sea and rivers are loaded with minerals, chemical compounds, etc. If one can perceive that the "water" isn't just water, that its solution of ions, elements, etc. then the use of magnets should make perfect sense.