Well, it's not ALL that helpful, but if you are competing for positions in persay a graduate school or medical school, it may make you stand out above the rest. And plus you'll have a reasonable knowledge of a certain field, usually a secondary subject that you're interested in. For me, I'll be going for a B.S. in Exercise Biology, but since I only need 108-124 units for that major, plus GE and such, I'll have plenty of units left to get a minor in Chemistry. It is required that I have 180 units to graduate with my bachelor's. I'll be applying for a graduate school for physical therapy, so it will possibly show the extra effort I put into my schoolwork.