Did you know that the United Nations used a Lego thing on a racism poster last week, and now claim they didn't consider the fact that Denmark (where Lego is made) is having a rough time because of those Mohammed cartoons. Not very happy at Lego, you better send your agent over.
I like this one. Spot on low-key, good colours and compostition.
I'm a big fan of Lego, but one thing to think about is that you want your backgrounds to either lend something to your subject or simply be backgrounds. In this image, the sharp contrasts in the black and white as well as the colored purple and red material take away from the lego man, which is already fairly underlit.
When I take pictures of toys, I often use small ultra-bright LED lights. I have a couple of magnetic ones that have snake-heads that work really great for creating dramatic spot type lighting. Check your local hardware store for something under 10 bucks... They are surprisingly strong.