I would be a huge advocate of water cooling if it wasn't for one issue.

Why run the risk of having all that conductive liquid circulating around your computer? I mean one drop leaks...*pop* and blue smoke, because you bridged two connections and fried your entire system. Doesn't sound like a good thought to me...

Ever thought about the liquids circulating in electronic machines in the kitchen?

Like what?

A Blender.

I was thinking more along the lines of electronic, not electric

I didn't know water circulated inside a blender. Thanks for that little factoid, Y&W.

Fridge freezer unit is what I think Mict is trying to point out. Or an AC unit. If the water cooling system is professionally made then I don't see that the possibility of leakage would be that off putting. A home made system on the other hand means you would have to be very careful with seals and tubing connections...

As long as you use distilled water it's no cause of concern (hint non-conductive)

I've filled my PSU with distilled water when the comp was on but nothing happened...

It was when I saw that a hose had got bent, I removed it and went to get a new one, then my sister went up and started the comp...