GrandCentral's theory of unified phone numbers

Not many new tech products and services make me think "Ooh, I must try that." GrandCentral is one. I just heard about it from David Pogue, who writes in the New York Times that

Millions of people have more than one phone number these days — home, work, cellular, hotel room, vacation home, yacht — and with great complexity comes great hassle. You have to check multiple answering machines. You miss calls when people try to reach you on your cell when you’re at home (or the other way around). You send around e-mail messages at work that say, “On Thursday from 5 to 8:30, I’ll be on my cell; for the rest of the weekend, call me at home.”

And when you switch your job, cellphone carrier or home city, you have to notify everyone you know that you have new phone numbers.

A new service called GrandCentral, now in its final weeks of public beta testing, solves all of these problems. It’s a rather brilliant melding of cellphone and the Internet.

Its motto, “One number for life,” pretty much says it all. At GrandCentral.com, you choose a new, single, unified phone number (more on this in a moment). You hand it out to everyone you know, instructing them to delete all your old numbers from their Rolodexes.

From now on, whenever somebody dials your new uninumber, all of your phones ring simultaneously, like something out of “The Lawnmower Man.”

No longer will anyone have to track you down by dialing each of your numbers in turn. No longer does it matter if you’re home, at work or on the road. Your new GrandCentral phone number will find you.

Some of GrandCentral's features look amazing. You can play your voice messages on the GrandCentral site, and download them as audio files. You can easily record any call in progress. You can listen live to someone leaving a message on your cell phone.

Here's the best part: Pogue says if you have only two numbers to unify, GrandCentral is free.