Using an array of 10 powerful radio telescopes, aimed at the galaxy BL Lacertae, the researchers studied a black hole just as it was sending forth a blazar jet.

BBC: Black holes reveal more secrets

Oh, and a fax machine for sending documents back and forth.

FORBES: Home Sales Down? Not For This Realtor

Why is the U.S. creating military units, stationing them overseas, and sending them back and forth for training to benefit the security of another nation, an advanced and wealthy country capable of defending itself?

FORBES: Why Are U.S. Troops Still In Korea?

Cynics may ask how a social network for two differs from simply sending text messages back and forth.

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