Corporate and nonprofit forays into social media are often awkward and clumsy - really, why does a fertilizer need a Twitter account? But the Atlanta History Center has figured it out. There's the world's busiest airport when it was basically just a tower and strip of asphalt. And there's Peachtree Street packed with men in fedoras and celebrating Japan's surrender in World War II. Oh, and here's an as-it-happened, liveblog reenacting the 1917 fire that consumed nearly 300 acres between the Old Fourth Ward and Midtown. By digging into its vaults and sharing historic photographs, audio files, relics, and other do-dads on Tumblr (and often with humor), the Buckhead-based center deftly manages to do what so many museums can't - become more than a building filled with exhibits. Not to mention tempting a younger generation to make the trek north on Peachtree and pay a visit.