If I'm really excited about a position, I'll write my own code sample before I go to an interview. I'll typically write either a simple igoogle module or possi

If I'm really excited about a position, I'll write my own code sample before I go to an interview. I'll typically write either a simple igoogle module or possibly a simple feature on my own website, proxying some of their calls through my own web server. I find it does a tremendous amount of good on both ends. It lets me explore their website and look at their apis, I get a better understanding of their tech stack, and by looking at their code (at least their client javascript code), I brush up on areas that they've tackled. On the company's end, we can dive into some tangible code that I've written and they can code review my work and ask technical questions based on that. It also shows them I'm serious and will hit the ground running. I much prefer talking about relevant code that I've just written to a trip to the whiteboard to answer an esoteric question or hard brain teaser. It's more like a real work environment and the questions, at least I think, are more authentic to the task: why did you implement that algorithm this way instead of another? what are the code's limitations or where can it be improved? how would it scale?