Vodafone has unleashed what it claims to be the world's first designated prepay phone that is aimed squarely at Facebook fans (the INQ Cloud Touch is also available on contract). Indeed, the handset itself has been designed in collaboration with the social networking giant and even features the iconic "F" logo as a separate button.The Vodafone 555 Blue (which sounds a bit like a 1980s porn movie, to be honest) is fairly basic in functionality and connectivity: There's a QWERTY keypad, 2.4-inch display, and 2-megapixel camera (with flash)It can play MP3s, WMAs and AACs through built-in music software, and its 40MB of on-board can be upgraded through SD card support (up to 16GB). There's also an FM radio and Bluetooth 2.1.And, of course, Facebook is built into its core, running from the off. Messages from your FB friends will appear in your inbox alongside emails. It also updates automatically in the background, so you can always keep informed of what's going on in your social networking world.There's also the\u00a0Opera Mini 5 web browser on board for internet tomfoolery. But it is only a 2.5G device, so it's not designed to munch away on massive amounts of data (just as well, really. As a pre-pay handset, you don't want to run out of credit quickly for phone calls, for example).Vodafone will be releasing the 555 Blue globally in the near future, through its own shops and online. Pricing is yet to be confirmed.