The Secret Energy Turbine (S.E.T. Small Wind Turbine) looks just like a traditional chimney pot, especially when the blades are turning which creates the appearance of a solid pot. Yet it houses an incredibly efficient vertical axis wind turbine that quietly delivers sufficient electricity to power domestic lighting and low input appliances such as computers and televisions.

Invisible roof tile repairs. Do away with unsightly lead straps which give the impression that the roof is unsafe and prone to further problems. Older buildings can look quaint. Lead straps in the roof make it look dilapidated.
Failsafe - Properly installed cannot fail. No comeback - Once installed, forget about them. No cost of return visit to repair. Silicon is not a tradesman's repair.