When I recently ordered battery-operated candles online, I came across an interesting novelty item. It is a water activated rose (about the size of your palm) that lights up, and changes colors. It is battery operated, but I don't see an access area to the batteries, so most likely when it finally burns out, you have to discard it.
You put the rose in water, and it begins to light up. It changes colors fairly rapidly, and includes red, blue, green, purple, turquoise white, and pink. It is simply beautiful, and fun to watch. The roses can be used as floating candles in a clear container, in pools, centerpieces, and ponds. You can also use them in bathtubs for decorative purposes, but I would not suggest that you bathe in the same water, because there is a warning about the batteries containing lead cadmium and mercury, so you should wash your hands after handling them.
These would make great party decorations, and would be so pretty for wedding receptions, or anniversary parties.
These color changing roses are very unique, and will fascinate young and old alike. I ordered several, and will always have some around. I put one in a margarita type glass by the tub while I was soaking, and it was very relaxing. They can be found online at http://www.bluw.com/floating-rose.html. I actually purchased mine at http://www.batteryoperatedcandles.net/mm5/merchant.mvc?Screen=SEARCH&Store_Code=BOC&Sort=&View=grid&Search=rose+floating (but right now they only seem to have the solid colors that light up, and not the changing color roses.)