But it's also a very complex system.

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The trouble is that it takes decades to develop a complex new defence system but threats change quickly.

ECONOMIST: Defence procurement

Green is realistic about the difficulty of getting users to trust a new, complex cryptographic system, but believes that adoption of Zerocoin is possible.

FORBES: Connect

The recognition isn't quite as good as CalliGrapher, but running CalliGrapher means using a Windows CE machine, an operating system that is far too complex for a mere electronic organizer.

FORBES: Scratch pads

And even the casual beach volleyball players and sometime indoor coaches admit they might have mastered the simple hitting and scoring system, but the complex signals players use, with their hands placed behind their bottoms, remain a tantalising mystery.

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