Glflegolas wrote:
Well, yes, but not for the reasons you think. Water is one of very few substances where the solid state is actually less dense than the liquid -- that's why ice floats atop water. It's also great at putting out fires (well, as long as it isn't a metal, electrical, or organic solvent fire), and is the only liquid where consumption of large quantities has only one side-effect: frequent bathroom trips.
Probably the most interesting thing about water, though, is this. If the most common liquid was something other than water -- maybe acetone (discounting the huge fire hazard) -- the ocean would freeze solid, as it would freeze from the bottom up. Eventually, all the acetone in the world would freeze into a great big solid chunk. In the summer, only the top few centimeters would thaw, and the world would be very cold as all that white frozen acetone would reflect the sun.
So, what I find most fascinating about water is the fact that if it didn't exist, there would not be any life on Earth, at least, not as we know it today. It's also good for sailing on to boot, and isn't poisonous. What's not to like?
@C2V: Seriously, you can smell water?! What does it smell like?
Actually, you can kill yourself with drinking water. A good working definition of poison is "too much."
The water molecule is incredibly active for just ten protons. It even has extraordinary heat capacity. We call it the universal solvent because it is pretty close - it would be more lethal than acetone to life based on another molecule. Life and geology on earth is severely restricted by water, but also enabled by its weirdness in detail.
BTW, after years of limiting my exposure to industrial solvents, I was edified to learn that my body produces acetone.