If you're familiar with safety spoons (spoons with heat sensitivity properties that turn white if the temperature is too high), you might be intrigued by Hansacanyon -- a line of color-altering, heat sensing faucets that do what the safety spoon does, albeit via an entirely different technology.
Hansa's line of faucets for sinks, baths and showers uses embedded LEDs and presumably some kind of internal thermometer to indicate water temperature. The magenta glow offers a visual cue that the water's too hot before you scald your skin.
Aside from the fun factor, there's the safety component and, as with the spoons, this is very useful for households with kids.
See Hansa's website for more information.
(Edited from a post originally published 8.31.06)
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I don't know about the faucet, but surely it's time to start a trend of using those brightly colored safety spoons with some sort of caldo-freddo dessert for adults.
Those are cool, as I don't have any kids I had never even heard of safety spoons, but I can definitely invision myself being totally enthralled by the colors in the spoons as well as the faucets:)
So I agree. Cool as all getup. But not new. This was being showcased on some other design sites a few months back. The kicker is.. try locating and buying one of these here in the good ol us of a. We were so jazzed by this when we first saw it. And then we started the hunt to get one ordered. Noooo luck. We ended up talking to a distributor in Vancouver who was having issues in getting pricing/etc.
Someone needs to do this for glass. The first rule of chemistry lab that I tell all my students is that hot glass looks exactly the same as cold glass. And there are still people who burn themselves each year...
Here's a version from ThinkGeek:
For the faucet:<A HREF="http://www.thinkgeek.com/homeoffice/kitchen/8122/">http://www.thinkgeek.com/homeoffice/kitchen/8122/</A>
For the shower:<A HREF="http://www.thinkgeek.com/homeoffice/lights/a446/">http://www.thinkgeek.com/homeoffice/lights/a446/</A>