Since the government has banned most sales of incandescent lightbulbs, newer technologies like CFL (Compact Fluorescent) and LED lights have taken its place. There are plenty of reasons not to like CFL, though. The light they produce is harsh, they contain Mercury so there are pollution issues, and they take time to "warm up" after being turned on. LED bulbs, on the other hand, take very little power and last for a very long time. The only issue with LED lightbulbs at this point is the heat they produce, requiring a large and expensive heat sink to be used.
Philips has created a new kind of LED, called the SlimStyle, and it's being sold exclusively at Home Depot. Since they've designed the bulb to not require a heat sink, the bulb can be sold for $10. The LED lights are actually in a circular ring around glass in the middle, which acts as a heat sync. It's a 60W equivalent light, and they're dimmable, which other LEDs aren't. Leo thinks this bulb is the way of the future when it comes time to replace bulbs.