major in math (vs. cs), take less classes (so i could work on my ideas), intern at start ups, study abroad (semester or 2) at a place I'd never even consider living in (because once you graduate, it probably ain't happening, for various reasons. In college, you still have a support system)

what i'd do the same: hang out almost exclusively with people outside my major. My college friends are writers, traders, architects, etc, and I've learned immensely from them during college, and afterwards.