My panel in Atlanta spent a while touching on PCI Compliance as it relates to a service opportunity. Anyone accepting credit cards is affected by PCI Compliance. New Edge Networks, an EarthLink company, has probably been in the forefront of this niche, carving out a major share of the retail connectivity space.
Accel just announced that their Layer 2 Wireless Broadband product has "exceeded the stringent security objectives and criteria set by the VISA Cardholder Information Security Program (CISP)."
If you provide connectivity to retail stores and they are using that broadband for credit card processing, you might want to think about PCI Compliance.