That is a nifty little gadget. I changed the link to the selling company's site so no one assumes the blog that you linked to is your own site.

I would *so* buy one of those if I could do it in person.

I just refuse to pay twice as much for shipping as the unit itself though.

Great idea. I'll definitely be keeping my eyes out for them locally.

I DID buy this for my best friend for her birthday.

It doesn't turn the color so much in sunlight or room light, but if the room is dark, it glows very powerfully. A good view of what it looks like in light is the bottom action shot at the link. But I reiterate, in the darkness it's very impressive.
The only problem then is you realize that nobody uses their sinks with the lights out.
I have one for my own sink, but it only turns the water blue(mine was cheaper). It's alot of fun. And the temperature ones do in fact change with temperature, set up is easy... I would suggest getting it if you don't mind getting used to bathing/brushing your teeth/washing your hands in the dark. I thought it would be cool if they had a showerhead like this.
Can be bought here.

If they had these when I was in my early 20's I would still be in the bathroom.

DEP still is in the bathroom...but that's from this post, not any colored water.

this will keep me from wasting water.

I think they have these things at 7-Eleven and McDonalds -- though theirs is brown, and the water is subsequently sold as 'coffee.'

Meh - We have one of those on the 30+ Bus