By David Sims, TMCnet Contributing Editor

A vanity number, as officials of Phone.com (News - Alert) say, is a phone number that can be communicated verbally using words, as opposed to just listing off numbers. For example, 1-800 BUY TOYS or the classic 1-800 FLOWERS. Which is a whole heck of a lot easier to remember than… than whatever the actual number is.

And that's not just common sense, it's been proven: "In a controlled test environment comparing the use of a vanity 800 number against a standard numeric phone number in a radio advertising campaign, 58 percent more calls came in via the vanity phone number," Phone.com officials say.

This should not be surprising as vanity 800 numbers are easier to remember than random sequences, and due to the fact that the sort of idiot savants who can instantly remember long number strings rarely call in for your product.

Obviously the 800 prefix is the most popular toll free brand, it's the "dot-com" of the phone world, but 888, 877, or 866 are being used now to the point where you'll get calls putting them in front of your word.

Okay, you don't need a toll-free number, your lazy cheapskate brother-in-law will rack up huge charges calling it and asking to speak to your wife. Fine. Still, a memorable phone number with staying power brings in more prospects, Phone.com says, adding "that's why you'll see taxi companies that rely on incoming calls using numbers like 877-7777." Random numeric numbers dilute your sales message because "hard to remember'" numbers need to be repeated more frequently to be effective.

Phone.com has offerings that let you use an existing number, which you may have had for years, or allow you to select a number in your local calling area or anywhere else in the US. "If you choose Virtual Office, you can also select Toll Free numbers and Vanity Toll Free numbers," company officials say, adding that "each plan includes at least one phone number."

Make sure it's a memorable one.