Yesterday's coverage of wireless telecommunications was pretty thick, and understandably so given the blockbuster deal between Cingular -- owned by SBC (NYSE:SBC) and BellSouth (NYSE:BLS) -- and AT&T Wireless (NYSE:AWE). Lost in the shuffle was a less important but nevertheless interesting feature on Forbes' website discussing mobile phone ringtones.

I spent three weeks working in a large, newsroom-style office in London in early 2002 and was struck by -- among other cultural differences -- the sheer variety of mobile phone ringtones I heard in any given day. Whereas in U.S. Fool HQ in late 2001 I could only remember an echo cavern of identical tones, in London I was seemingly surrounded by dozens of chirpy radios, each tuned to a different station. Even now, leafing through the back pages of England's FourFourTwo magazine, there are all manner of ads ready to help your phone's milkshake bring all the boys to the yard with a variety of popular song tunes.

The phenomenon is growing Stateside now, as Chana Schoenberger noted yesterday in Forbes. Some $2.5 billion was spent on ringtones worldwide last year, her article said, with $80 million of that coming from the U.S. -- up from just $20 million in 2002. That's seen jumping another $20 million this year, which is no surprise given that they're relatively inexpensive (generally between $1 and $3), even if the idea may seem a little strange at first. New phones can even handle song files of MP3-like quality.

The confluence of pop music with the generally young demographic that uses mobile phones and shops electronically would seem to point to the potential for pretty easy, high-margin money to be made here. Also worth watching out for are such similarly downloaded services as games and wallpapers, which let users personalize their phones even further.

Already mobile phone makers such as Nokia (NYSE:NOK) and Motorola (NYSE:MOT), the music industry, and service providers are catching on -- as have some unauthorized retailers who've apparently found a new battleground to contest in the copyright wars.

So don't be left out: From Outkast's "Hey Ya" to Led Zeppelin's "Stairway to Heaven" to "You're Gonna Miss Me When I'm Gone" by Brooks & Dunn, there's a little something for everyone's phone.

Keeping yours on vibrate? Share your stories of movie theater hell on our Wireless World discussion board.

Fool contributor Dave Marino-Nachison doesn't own any of the companies in this story. He can be reached via email.