Computer programming experience suggests to your potential employer that you have problem-solving abilities, and a capacity to work independently and creatively. Develop knowledge in the areas which interest you. If your interests are biological, then take a lot of biology coursework. If your interests are in health care reform, then take a lot of economics. Take additional course work in your department's specialty area.
Most departments have something they pride themselves on doing exceptionally well.
You are in the pre-eminent cognitive psychology department in the country. You have an opportunity to work with some of the most gifted cognitive researchers in the world. Seek out and get to know the administrative people who manage the undergraduate research programs at your institution. Talk to them about the kinds of opportunities that are available to you. Serve as a research assistant.