Forget voice, M2M is where the mobile big money is...

With 3G yet to make its mark significantly and subscriber numbers levelling off in West European, US and Japanese markets, mobile service providers are looking for the next cash cow to milk.

And research from e-principles reveals that M2M (machine to machine, man to machine or machine to man) revenues could reach $20bn by 2008 and could mean up to $74bn in service provider revenue.

It's a phenomenon that Robin Duke-Woolley, director at e-principles, calls "the new business opportunity in wireless" and he predicts that the number of cellular M2M connections will overtake the number of mobile subscribers in key markets within the next 8 years.

Just as the traditional mobile quickly became pretty much unavoidable and indispensable, M2M has the potential to go the same way, according to the Cellular M2M: Generating Profits from Business Opportunities report. Users are already dipping their toes in the M2M water by installing the technology in cars to monitor drivers' behaviour for their insurance, monitoring crop and water levels, as well as checking on goods on the move.

As well as making wireless companies very happy and giving them a few extra coppers to play with, M2M may actually start shaping the world of technology as we know it.

Unlike its consumer mobile equivalent, M2M means sending small volumes of data, often and making it universally available – and it's these requirements that will mean a radical overhaul for mobile providers, as new services and systems spring up to make sure the right data finds its way into the hands of the person who needs it at the time they need it.