Back in the day, there was a great game called Lemmings. On each level, your poor lemmings faced a myriad of challenges, but fortunately, they had certain skills that you could control. For instance, some could dig, some could build, and others could blow things up. Your job was to get a set of lemmings home by utilizing their skills.
Anyway, some guy pseudonamed "crisp" has done a brilliant version in DHTML (Dynamic HTML). It's true to the game I remember and is just as fun. I'm constantly amazed at the great stuff people can build in DHTML. Check out DHTML Asteroids too. It's an old demonstration of IE's abilities by Michael Wallent (former Product Unit Manager of Internet Explorer and now the General Manager of our Avalon effort.) It runs a bit fast on modern hardware, but it's still cool.
(Note, the screenshot above has been scaled down a bit to fit here. The real thing looks better.)