Barcelona (Spain) - At the 3GSM world conference, Samsung is showing off what it claims is the world's thinnest consumer cell phone, at a thickness not much bigger than a layer of tree bark.

The U100, part of Samsung's Ultra Edition II line of sleek handsets, measures in at just 5.9 millimeters thick. That's about the same as a Type II Compact Flash card, and it's half as thick as what the iPhone is reported to be.

According to Samsung, the handset is a whole millimeter thinner than the current slimness record holder, which is also a Samsung. Sleek phones became increasingly popular after devices like Motorola's Razr and the iPod Nano elicited a ton of positive public response. A battle for the slimmest phone has been underway ever since.

Also at 3GSM, Samsung unveiled the F700, F520, and F510 multimedia phones, which are all focused on mobile video and planned for a 2007 release. The U100, which will be hitting Europe this spring, currently has no defined US release date.

Other features in the U100 include a 3 megapixel camera and music/video playback. It comes packed with 80 MB of internal storage and is Bluetooth enabled.