Investors have many sector funds to choose from, spanning eight different Morningstar categories: communications, financials, healthcare, natural resources, precious metals, real estate, technology, and utilities. Some sector funds focus more narrowly, homing in on a particular subsector of an industry. For example, the GenomicsFund GENEX is categorized as a health-care fund, but it invests almost exclusively in genomics or genomics-related stocks—a fairly small industry. Then there's Fidelity Select Wireless FWRLX, which is a telecom fund that focuses entirely on wireless service providers and gearmakers. Given their more concentrated focus, these funds are often even more volatile than the typical sector fund.