If you are a Harvard undergraduate student interested in doing a research project in Human-Computer Interaction or applied Machine Learning, or--ideally--a combination of the two, please talk to me. I have a number of project ideas that you can contribute to, or you can propose your own. To get a sense of the style of work that we do, see some of our current and recent projects, but note that this is not an exhaustive list.
In general, the best time to join a research group is at the end of your sophomore year or at the beginning of your junior year. By that time, you should have enough technical background to contribute to a project, and still enough time left at Harvard to see the fruits of your labor. Ideal candidates would have taken at least one of CS 179, CS 181, or CS 182.