Greg Bower(ph), of the International Association of Bomb Technicians and Investigators, says nitroglycerin is usually too unstable to handle safely.

NPR: It's Hard to Spot a Liquid Threat to Airline Safety

In case you've still not pieced it together, there are simply too many variables to safely say that one provider is right for every fan of HD.

ENGADGET: blogger-avatar

The moans about their inability to make profits safely sounds all too close to the noises from old-style airlines before the arrival of low-cost carriers.

ECONOMIST: Bank regulations

However, there might actually be benefits for taxpayers and others shareholders in doing so, our correspondent added, because some banks had become too big and complicated to manage safely.

BBC: Archbishop's warning over economic 'depression'

To elucidate, some banks have become too big and complicated to manage safely - which would perhaps be the lesson of the 2007-08 debacles at UBS, RBS and Citigroup, inter alia.

BBC: Should bishops run the banks?

For example, we can now safely say that HP paid too much for Autonomy.

FORBES: Why Cisco's Future Is Brighter With New Cloudy Deal

Happily, the difficult steps needed to get safely to low numbers would all be needed for zero too.

ECONOMIST: Getting to zero

You can safely expect more puns around digital highways, driving data and speeding up innovation to be not too far away.

BBC: 'Every new car' connected to web by 2014