Being both useful and cheap, today's tech deal ticks all the right boxes and it can be yours for under a fiver.

The Santok mini car charger is just £4.95 from (that's the cheap bit) and can replace you car's cigarette lighter with the plug-in USB socket to create a simple way to charge mobile phones or other gadgets (the useful bit).

The device's space-saving design also gives you the benefit that if your car's cigarette lighter is located inside an ashtray or has a flip down cover it should still fit.

Suitable for any gadget that's compatible with a USB - so good for most MP3 players and certain phones - this appears to be a good solution for keeping any power-hungry equipment topped up while you're out and about.