I'm becoming something of a granola-head. The house is full of compact flourescent bulbs (but utilities are included in the rent), we don't own a car, and I just bought a vegetarian turkey for Thanksgiving.
But the new addition I love the most is our low-flow shower head. So make that a granola geek. It tops out at 2.25 gpm, but to do that you get such a torrent of mist -- the effect is like standing too close to a big waterfall -- that the shower curtain flutters like a flag. I estimate I use half that much water, and get squeaky clean, with less energy and steam besides. (The apartment's ventilation isn't great.)
The kicker is the button that left me turn off the flow while soaping up. As a child of a Coastie, I was taught the value of sea showers, but this was impractical if that meant cutting the water off at the tub, only to face a scalding or freezing to rinse off.
I recommend its design and function. Plus, it is American made and quite solid. For less than $20 shipped, there may be a gift idea in it.