Held in Las Vegas every January, CES is the world's biggest technology trade show, featuring everything from huge television and smart washing machines, to fitness trackers and self-driving cars. Here are five of the most interesting stories from this year's show.

Sony brings back the 90s with $1,200 Walkman

Sony brought back the 90s at CES this year, announcing a new, super-high end Walkman music player. It plays uncompressed music at higher than CD quality and has 128GB of storage, but at $1,200 (£790), it certainly isn't cheap.

Mercedes' concept car is a lounge on wheels

Self-driving cars are making their presence felt at technology shows more and more each year, and at CES this week Mercedes showed off the F015, a concept vehicle that is part car, part lounge.

Once free from the complicated roads of towns and cities, the F015 can drive itself, leaving the driver fre to work, or fold the steering wheel away, turn their seat around and chat with their passengers. It combines a hydrogen fuel cell with two electric motors and is claimed to have a range of more than 600 miles.

Autonmous Audi drives 500 miles to Vegas

Audi also used CES to showcase its latest development in autonomous driving. A specially modified A7 Sportback took a group of journalists on a 550-mile road trip to Vegas without incident, and Audi claims the technology used is production ready, so look out for self-driving options appearing in your local dealership soon.

LG bets big on OLED televisions (again), but fails to mention prices or release dates

LG bet big on OLED televisions this year. The technology has been touted as the next big thing for years now, but has always been too expensive to enter the mainstream.

LG hasn't let that stop it though, having announced seven massive new OLED screens at CES this year, including one which transforms flat to curved at the touch of a button.

The company is pumping $600m into OLED production, but with no prices or release dates announced in Vegas we could be left wiaitng yet another year before the technology goes mainstream.

Belty the smart belt

And finally...CES wouldn't be complete without something out of the ordinary and this year it's Belty, a smartbelt which automatically slackens when you eat too much, tracks your activity, and politely nudges you when it thinks you should be moving more.

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