Focusing on the fact that most people usually boil more water than they need, a British firm has designed Eco Kettle, which has a boiling chamber that is separate from the main water reservoir. That way, you can boil only the exact amount of water you need.
True, you can always conserve energy with your standard kettle by filling it up with only as much water as you need. But if, say, you are in an office environment and your water source is far from where your kettle is located, Eco Kettle would save you from making unnecessary trips to your water source.
This can either be a good or bad thing. Sometimes, having to fetch water is a good excuse to get up and stretch your legs. On the other hand, Eco Kettle's combination of convenience and saving energy is undoubtedly hard to resist for many of us.