We are fans of LED lamps. The enable you to change the mood and atmosphere of a room quite easily. Rainbow Star Lamps from Lumenworks are color-changing LED lamps. Just like the LivingColor lights from Philips, these lights will work hard at changing the ambiance of any room. Unlike the Philips lamp, they are available at a fraction of the price.
These sorts of lights would fit well into a home office, to give you time to think and ruminate over problems or new challenges. We've found that just altering the lights in a working room will make you work slightly more efficiently. They could also be used as ambient lighting in a home theater room. Since they are cheaper to buy than the other LED lamps on the market, they are perfect to be set around your HDTV, so simulate Ambilight, a low intensity light that goes behind your screen when every other light is dark. They would also work well in a bedroom.
The Rainbow Star lamps are minimal, modern lighting fixtures, which can be set in any of 7 different colors. You can switch between colors, or set them to cycle gradually between them. Each light is encased in a glossy hard acrylic shell, which seems to float on a square metal pedestal. Their height is just under 10". Another interesting feature, is that each light has a small nightlight built into the base, which starts up as soon as the room goes dark.
Each light has a hidden AA battery compartment, which lets you use the light without always being tethered to a wall socket. A single charge should last about 4 to 5 hours. For now, they aren't available outside Taiwan, but if you understand Mandarin, you can head over to PCHome to purchase them for about $86.