From Thinkgeek:
It’s time to bring the potion home with you with this LED Potion Desk Lamp. This little bottle may not look like much, but it’s filled with magic (Ed. note: it might technically be science and/or resin). Tap the base and invoke the word “LUMOS!” to light it up. Tap it and whisper “Colovaria” to make it magically change color. Give it a tap and say, “I don’t actually have to say anything because this lamp is touch-activated” to switch colors again. That’s right. It’s like an old-fashioned tap-on/tap-off light except you tap this one to change modes: solid red, green, yellow, blue, or a slow fade across the spectrum. A sensor combined with an LED in the base does all the work for you. All you have to do is plug it in and let the magic happen.