Being lost in a strange town on the way to a meeting is not fun.

Being lost driving to an airport to catch a flight is even worse. So the last time it happened to me, I made a mental note to pack a portable GPS navigation system next time.

In spite of concerns about forsaking a map for another electronic gadget, I have been a convert to GPS navigation systems for years.

I have used several after-market add-ons. My favourites include the in-dash Eclipse AVN7000 system and Tom Tom's Go 910.

The latter, which costs about $500, comes with maps of Europe, the US and Canada on its internal 20Gb hard disk and a built-in MP3 player. It also features LCD touch screen, a menu system that makes it easy to adjust settings and enter destinations, and sophisticated voice technology.

Other manufacturers, such as Garmin (www.garmin.com) and Magellan (www.magellangps.com), have mostly caught up, building sophisticated hard drive-based portable units that attach to the windscreen and can be moved between vehicles.

Newcomers, such as Cobra (www.cobra.com), Lowrance Electronics (www.lowrance.com) and Michelin (www.viamichelin.com), have also emerged.

These battery-powered devices are equally useful for holding as you walk along the street or mounting above a dashboard, usually using a suction-cup arm. Garmin's popular n�vi GPS units fall into this category and include devices for both European and US markets.

The recently launched n�vi 670 comes loaded with US and European maps, a 4.3in widescreen display, Bluetooth wireless connectivity and an integrated FM traffic message channel receiver that helps route users round traffic jams. It has a retail price of $1,179 in the US where it has just gone on sale.

Pioneer's AVIC-S1 (www.pioneer.com), costs about $400. It has a 3.5in touch screen and a barrel-style jog wheel. The maps and database of points of interest are stored on 2Gb of flash memory, meaning it is ready to use as soon as you press the power-on button, simple to operate and the turn-by-turn voice directions are accurate.

Increasingly, these handy personal GPSs have multimedia capabilities, and can play MP3 tracks and display digital images.

Both Delphi's NAV200 (www.delphi.com) and Mio Technology's DigiWalker H610 (www.mioGPS.com) come with maps loaded and have SD card slots for loading audio, video and image files. At $300 the NAV200 is exceptionally good value, but the $449 DigiWalker is significantly more compact.

HP's personal digital assistant-style iPAQ rx5935 Travel Companion, is an interesting option at $600. This device, powered by Windows CE 5, is a fully featured PDA but also has WiFi and Bluetooth connectivity, a suite of personal productivity tools and comes with a big touch screen, sensitive chipset and Tom Tom GPS software.

I have also been testing the new Pocket LOOX N100 from Fujitsu Siemens, one of the smallest and lightest personal GPS unit s. It can slip into a shirt pocket and comes with advanced features and produces 3D maps on its 2.8in touch screen. It is built around a Samsung 300MHz processor running Windows CE 5.0.

The N100 features the SiRFStar III GPS chipset and supports WAAS and EGNOS technologies. It also comes with a built-in MP3 player and a miniSD card slot to add extra storage capacity. Overall, the N100 is a delight to use and good value at $380.

Also consider smartphones, such as the new BlackBerry 8800, which features Tele­Nav's software, or Nokia's 6110 Navigator.