As cellular phone rates have lowered and access has become pervasive, the reasons for making a cell phone call have expanded from event-driven planning conversations to a kind of verbal, geo-locator service.

You see this geo-locator service use as soon as your plane lands, and the cell phones come out. Or, as school lets out for the day. Or, just for the heck of it, every half hour.

Or, if you live in a city with mass transit like I do, it isn't uncommon to see high-school and college students call their friends every third stop, advising them of their whereabouts.

Today, the geo-locator functionality of cell phones took on an amplified, if tragic meaning. As you probably know by now, there were a string of fatal subway and bus bombings in London. Given that they occurred in the morning rush hour, it would not be unfair to assume that hundreds of thousands of London commuters were in transit when the violence struck.

On a terrible day such as today, six things are likely to happen:

*As news accounts of the bombings reach loved ones and friends of those in transit, their first reaction will be to try and call the cell numbers of the people they care about;

*Those who manage to escape injury will call their friends and loved ones to assure them they are OK;

*Those near the scene will use their cell to call emergency responder agencies with updates and pleas for additional help for the wounded;

*Some emergency responders will use the cell network for communications;

*Emergency responder agencies and hospitals will be flooded with mobile calls from anxious, on-the-go friends and relatives who cannot reach the people they care about;

*Cellular networks will be flooded with text messages to and from commuters, and sometimes to each other.

Add up all these stark reasons, and you'll have a day such as today, one which U.K.-based cellular carriers won't ever forget.

In fact, London's telco networks swamped,an article just posted on the technology section of the (Toronto) Globe and Mail's Web site attests to this fact.

According to the G&M's Catherine McLean and Scott Deveau:

Wireless carrier Orange reported double the amount of daily traffic;

Wireless provider O2 experienced call volumes more than twoce that of normal weekday levels, and compensated by putting twice the traffic on the same bandwidth;

BT Mobile reported some uncompleted calls due to network congestion, and;

Vodafone UK experienced network congestion and posted a message on its website asking all of its central London customers to "avoid making unnecessary or lengthy phone calls."

Let's hope we see many more days where more cell calls are made for trivial reasons- and a day like today never happens again.