The new Wireless Pointer-style dongle from T-Mobile can show you the best location for picking up a 3G signal, just like a divining rod twitches towards a source of water.
The Wireless Pointer converts a 3G signal into a Wi-Fi bubble that beams the Intertubes to up to five devices. But it has an added signal indicator, which shows you where you can pick up the best 3G connection. This allows you to move the pointer around until you find a 3G sweet spot, like when your dad made you wave the aerial around to get a better TV signal.
The Wireless Pointer will be available in T-Mobile stores from free on a 24-month contract, or £60 plus a £10 top-up on T-Mobile's pay per day service.
These sorts of gadgets are always a good option if you think you're likely to have more than one device you need to be connected to the Internet, and you're often on the move. You'll have 5 hours of browsing before you need to charge it, and it offers download speeds of up to 4.5Mbps. It'll work with Windows and Mac computers.
To be perfectly honest, we're not sure how much difference that signal indicator will make -- you'd think moving the thing this way and that wouldn't make that much difference. Hopefully you won't end up in a Mr Bean-style pickle trying to find a signal.
There are other options. Three and have both had MiFi devices available for a while now, which do exactly the same job as the Wireless Pointer, but without the signal gimmick. You can also buy an in which you can stick any SIM card, but these usually cost a fair chunk more than if you buy one locked to a network.
If you particularly like T-Mobile's broadband service, this would be a fair enough option, but it'll pay to shop around.