When the first cellular telephones rolled into the market in the 1990's, nobody ever expected that those clunky black boxes with their electronic shrills would develop into sleek, powerful machines that could (aside from sending and receiving calls) take a picture, make a video, and sing.

Yes, sing. Today's ring tones have the audio quality equal to the sounds we hear in real life. Say goodbye to the monophonic ring tones and its R2D2-like beeps and whistles. And even the polyphonic ring tones sound too sharp for our tastes, more like a music box than, well, music. Now, the standard for ring tones is realtones--as melodic and realistic as the songs on the radio (or the sounds of the farm, depending on which real tone you want).

Realtones are also called true tones, voice tones and name tones. But, to borrow a phrase from Shakespeare, "A tone by any other name would sound as sweet." The popularity of realtones has reached a point that it's actually formed a large chunk of the profits of the cellular phone industry.

While there are many sites that provide realtones for free (preferring to get their earnings from clicks, ads or links) many mobile phone users actually don't mind paying good money for a song that they like.

Just look at the industry reports. A staggering 60% of the total revenues from the mobile phone ring tone industry are from realtones. They are clearly outselling monophonic ring tones and polyphonic ring tones, which only from 33% of the revenues combined. The remaining seven percent of the total revenues were generated from the download of callback tones.

That means over half of the millions of cellular phone users are "keeping it real". People are addicted to realtones, and will continue downloading tones even if their telephones already packed with a list of songs that would make a DJ proud. In fact, even if cellular telephones are already programmed with its own generic set of ring tones, most prefer to replace them with realtones that they love. It's part of the whole appeal of being able to personalize your phone.

There are hundreds of thousands of realtones available on the web. The most popular are from the songs of pop artists like Gwen Stefani, Destiny's Child. Of course, it all depends on who's leading the pop charts. Gwen Stefani's Hollaback Girl, Cater 2 U by Destiny's Child, and We Belong Together by Mariah Carey were all big hits in 2005, so it's not surprising that people want to play them on their telephones.

Next to pop, the most popular realtones are from Rap, Hip Hop and Punk.All in all, about 76% of real tone revenues are from actual songs. Studies show that there's a relationship between the songs that are downloaded for iPods and the songs downloaded for realtones. Generally, a music fan will want to have both on his gadgets--one to listen to, and an excerpt to play on the phone.

However, there are other types of realtones as well. Around 11% of the revenues in realtones were actually voice tones: celebrities saying hi, excerpts from movies.