Technofile: It was so addictive that it came to be called the "CrackBerry". But now the BlackBerry, used by so many executives to get their e-mail while on the move, is being squeezed by a wave of lawsuits and competition from new devices, writes Mike Butcher.

BlackBerry maker Research In Motion (RIM) is currently fighting for its life, after losing its patent battle with another firm, NTP, in the US. NTP disputed the BlackBerry patent on its all-important push e-mail service. It was this single feature - which meant that your BlackBerry would buzz the moment you received an e-mail - which saw RIM become so successful.

However, RIM faces a shutdown of its push e-mail service if the two sides fail to settle their dispute. The next deadline will be February 24th, where a US judge could issue the closure order.

Meanwhile, in the UK and Germany, BlackBerry has won its patent fights with the Luxembourg-based patent holding company, InPro Licensing.

But whether or not RIM manages to get out of this mess, a host of digital hyenas are hanging around waiting for the old beast to go lame. The latest to bound out of the long grass is the Sony Ericsson M600 (price yet to be announced).

Built from the ground up for messaging - the BlackBerry's forte - the M600 trumps the old timer with added touch-screen and handwriting recognition capabilities. It even sports the two letters per key of the latest BlackBerries.

RIM can take comfort from the fact that its BlackBerry connect service will be featured in the M600, which includes the ability to synchronise your e-mail with your PC. But Sony Ericsson is hedging its bets and supports multiple push e-mail solutions as well, including Microsoft Exchange ActiveSync, so you'll still be supported, whatever happens to RIM.

Sony Ericsson puts the market for business e-mail users around the globe at 650 million, so it's no wonder that the competition to create a BlackBerry killer is hotting up.

But it also has a little something up its sleeve. This is a 3G-capable mobile, and therefore sports much faster access to the web and e-mail.

Outside of that, there's 80MB of onboard memory, expandible with the - tediously non-standard - Sony Memory Stick Micro USB 2.0 and infrared. A manageable 15mm thick, it also has a three-way jog dial to control the menu and a 2.6-inch colour screen.

Of course, with no camera, this is one phone that will be underwhelming for the average consumer. However, at least you can have some fun during that budget meeting, with support for a range of music formats, including MP3 and 3D games.

The M600 is available in granite black and crystal white and will start shipping in the second quarter of 2006. For the average caffeine-addicted, e-mail obsessed executive, it's the business.

Correction: Last week's column should have included reference to the Maplin Electronics' 8-inch A13FG LCD DVB-TV, which costs around €290, as opposed to the Morphy Richards flip-down TV