It has an enormous ability to absorb and transmit energy. For example the amount of energy it would take to melt 1 kilogram of ice at zero degrees Celius would be enough to lower the temperature of 1 kilogram of Aluminum over 570 degrees Celsius. This is why water is ideal as a insulation or a heat dissipation source. It holds more heat than just about anything. This is odd because there is nothing in its chemical makeup or structure that justifies this ability to hold so much heat.
Water reacts with more substances than any other compound.
It reacts physically with several compounds to add to their crystal structure. Compounds like copper and magnesium sulfate are two examples of many compounds that almost always found in nature with water molecules physically attached to their crytal structure. Some of these compounds, have water as such an important part of their structure that they will even extract all available moisture from the air. These compound are natural dehumidifiers, dependent on water to complete their structure. Water also reacts chemically with many substances, creating new substances or compounds.