The Radar: Calgary’s Singing Tweets, Real Cost of RTW Travel, Paris Launches Electric Car Share

• Tweets have never sounded so good. The Calgary Philharmonic asked its Twitter fans to share tips for keeping warm during the winter months. The choir delivered the responses in an unconventional way– singing the tweets to the tune of O Fortuna! Watch this fun video. [Miss Cellania]

• How much does it really cost to take a round the world trip? Bootsnall asks real live RTW travelers to share the specifics of their budgets (per person, per day) and tips for sticking to it. [BootsnAll]

• Coming off the success of its bike rental system, Paris launched the first phase of its electric car sharing program, Autolib, by rolling out 250 models on the street last week. Autolib is expected to add 2,000 more vehicles to the roads by this coming summer. [Yahoo]

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