DVT kills many. As far as I've heard, no one's yet collapsed with a bad case of DVD after stepping off the plane.

I've been flying a lot recently (US, Singapore, New Zealand - so all long-haul), and lugging my PowerBook around with me. As it's tricky even getting a pair of shoes onto a plane these days, my arsenal of laptop peripherals should alarm baggage checkers - although strangely I've never been stopped and asked about the ticking ball of batteries, flashing hubs, and miles of twisted cord and cable that are squeezed into my smart laptop case. If ever a package appeared like a technically complex bomb, the inside of my carry-on case is it.

There's a couple of retractable modem cables (just in case I end up in a hotel or relative's house horrifyingly devoid of broadband), tens of metres of ethernet cable (hotels often forget to place the network port anywhere near a power point), card reader, mouse, spare batteries, and power cords.

There's at least a dozen continental and transatlantic travel adaptors mixed in - I always freak out at the Dixons in Departures, fearing I've loaded my bag with only French-style plug adaptors for a trip to California, or not remembering which type works down under. Some have so many sharp points they could be used to take out a squad of armed air marshals.

I'm sometimes asked by uniformed officials to open this bag of techno tricks and remove the PowerBook. After a few taps, the guy asks me to turn it on - meaning a lot less time for me to browse the embossed gold-lettering of books by John Grisham and Clive Cussler, or marvel at the number of tomes on Hitler and East End gangsters in the airport store. But apart from a rummage and fumble, the rest of the stuff in there is left alone. I could have packed a few pounds of Semtex for all they care.

But once you're actually on the plane, the merest sight of anything vaguely technical gets you picked out for scowls and tuts from assorted members of the cabin crew. While you sit there red-faced and holding your iPod, with all the other passengers joining in the chorus of shock and rising anger that you're putting their lives in danger, it's easy to get a little miffed yourself. It's far more likely that the tiny seats and evil recliners in front of you will do more damage than if you switch on your iPod, walkman, or mobile phone. DVT kills many. As far as I've heard, no one's yet collapsed with a bad case of DVD after stepping off the plane.

Once you're in flight, most airlines allow you to switch on your PDA or laptop. But many of today's technologies that we couldn't do without on land are still banned in the skies. For example, there's no such thing as Wi-Fi on the vast majority of routes. Using the wireless functions common on a variety of devices - such as laptops, PDAs, and mobiles - is banned on airplanes due to concerns that they emit radio waves that could interfere with the plane's communication and navigation systems.

However, we may be able to network with the first-class section in the future, as an advisory committee to the US Federal Aviation Administration (FAA) is expected to review the use of wireless devices on airplanes before the summer. In 1996, the advisory group told the FAA that it couldn't rule out the possibility of interference caused by the use of wireless electronics. If there's the slightest chance that your harmless Bluetooth transaction across the aisles will send the jumbo into a tail-spin, Wi-Fi will remain banned from the clouds forever. There's little point firing-up your mobile if the last thing you use it for is to take a picture of your kids falling 37,000 feet to earth.

Some airlines now allow passengers to use mobile phones once the plane has touched down. The Joint Aviation Authorities - the European equivalent of the FAA - allows use of Bluetooth devices during "non-critical" flight times by some European airlines. So far, no airlines have approved the use of wireless devices while airborne, mainly because they can't afford the expensive safety tests.

Any policy amendments are unlikely to occur before 2007. Imagine all the new devices that will be on offer by then, and the new-fangled features on our phones. Despite the lax checking of high-tech laptop bags being a far-greater danger than a PDA synching with a cell phone over the Atlantic, I'm not optimistic about us being able to use any of this stuff between descent and the baggage-reclaim hall. In the meantime, we'll just have to stare at pictures of teddy bears dressed up as pilots, and try to get the circulation going again in our legs.