Many oppose workplace surveillance, because of the inherent dehumanizing effect it has and the relentless pressure it brings.

But it's on the rise around the world as firms look to become more efficient by squeezing more productivity from their workers.

More than half of companies with over $750m in annual revenue used "non-traditional" monitoring techniques on staff last year.

Monitoring employee performance gives firms the ability to assess how their staff are performing and interacting, which can be good for both the firm and employees themselves.

A growing number of analytics companies offer this service.

They gather "data exhaust" left by employees' email and instant messaging apps, and use name badges equipped with radio-frequency identification devices and microphones.

These can check how much time you spend talking, your volume and tone of voice, even if you do not dominate conversations.

While this may sound intrusive, exponents argue that it can also protect employees against bullying and sexual harassment.

Some of this data analysis can produce unexpected results.

For example, it was found that people who sat at 12-person lunch tables tended to interact, share ideas more and outperform those who regularly sat at four-person tables, a fact that would probably have gone undetected without such data analysis.