Then, twice daily, the usage record is sent to the designated mobile phone or e-mail address of family or friend.

ECONOMIST: The grey market

The subway network, known as the Tube, will be congested and may break the all-time usage record of 4.31 million passengers set on 2 August 2012.

BBC: Navigating the London 2012 exodus

Record usage caused delays and problems on hurricane and news sites across the country.

CNN: Hurricane Floyd wallops Web

In its simplest form, it lets your "smart" electric meter talk back to the utility and record your usage by hour, so you can adjust your habits to take advantage of lower, off-peak rates.

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