A report by BusinessWeek says "employees in HP's PC division are exploring the possibility of building a mass-market operating system. HP's software would be based on Linux, but it would be simpler and easier for mainstream users." The threat is simple: A sub-$1,000 MacBook would knock a huge hole in HP's own notebook sales. Apple is only $100 away from that goal. The division's CTO insists "it's about innovating on top of Vista." But on top of is a misleading preposition for some of his company's modifications, which bypass Vista's built-in photo and video apps in favor of HP's own. (Illustration by Paul Blow/BusinessWeek)