I'm currently living in Stockholm, and as I write this post, some ultra-spicy Thai ramen is making my lips tingle.
The first time I saw my Swedish friend boil water in Sweden, I was surprised. He matter-of-fact-ly filled an electric kettle, poured a centimeter or two of water in the bottom of a pot, and set the pot on the stove over high heat while the electric kettle was boiling. Within minutes the kettle was finished, he poured the water into the pre-heated pot and voila, instant rolling boil.
This method is particular useful when you'd like to eat the quickest of quick foods: ramen. Now, I won't lie to you and say that I don't eat ramen. In fact, there are just some days when you're feeling lazy and there are no leftovers. However, I punch up my ramen by throwing in some frozen spinach (I always have some in the freezer) or any other vegetable I happen to have that will cook up fast, and then poach an egg while it's cooking. This guarantees at least a bit of nutrition, I promise!
According to my boyfriend, using an electric kettle is the most energy efficient way of boiling water. According to other studies, boiling more water than you need is a Europe-wide problem, so you should know exactly what you need. I know I need about an 8 on my Bodum kettle to make a full pot of tea.
While I was in New York, I was impressed by my sister's All-clad pot. It retained heat at such an amazing rate. I can only think that having a heat efficient pots and pans is not only environmentally conscious, but also works as a great boon to being able to control your cooking. It's definitely on my to-buy list.
Though some food recipes have discussed making your own hay box (lining a box with copious amounts of hay) to cook your food to be the most energy efficient, I haven't gotten that far yet. But! I have been suitably impressed upon to start poaching eggs by bringing the water to a boil and then letting the eggs sit in the hot water until they're finished (4-6 minutes) -- the same with boiled eggs.
Cutting back on meat is the most environmentally conscious gesture you can make, but Hugh Fearnley-Whittingstall has also pointed out that you can choose meats which are the most energy efficient in terms of the environment like pork and chicken. On an entirely unrelated note, apparently lamb is the most likely to be treated the best out of all the possible animal abuses since lamb doesn't thrive in poor conditions.