[skylark]

From sitting on both sides of the table, here's the gist of what I'm expecting to hear:

"Most recently I've been working at <company> on <short summary of project>. When I was there, I <two to three things I did which demonstrate that I'm awesome>. In my spare time I've been <something related to programming>."

The point of the question is to get you comfortable with the interview and give you the chance to say a few words on your own terms. The best thing you can do is show me you're someone who can effectively execute on a project, and give me some hooks that we can talk about in more detail.

Don't overthink it. It's an elevator pitch - it shouldn't take more than a minute or two.