12. (TIE) This resort-like estate is designed for entertaining both private and corporate guests in Los Altos Hills, one of Silicon Valley's most exclusive residential communities. The home is owned by tech entrepreneur Kumar Malavalli, founder of Brocade Communications Systems and current head of venture capital firm VKRM.
Price: $88 million
Highlights include an indoor pool with a retractable roof, guest suites with their own patios and bathrooms, freestanding office building for meetings, and easy access to major airports.