MyShot, National Geographic’s popular social hub that allows users to submit and vote on photos, and YourShot, the related submission site—have been two of the magazine industry’s few unmitigated successes on the Web.Now, the magazine is offering readers an opportunity to customize the cover of a special print issue—National Geographic’s Your Shot—that will feature “101 of the best readers’ photographs submitted to National Geographic magazine over the past three years.”Wired, you might recall, was one of (if not the) first national magazine to allow readers to customize a cover. The July 2007 project—funded by Xerox—netted Wired great press, but pulling together the issue, as one former staffer told me, was a “logistical nightmare.”National Geographic, though, might be looking for some incremental revenue, too. Via the press release:Looking for a unique Father’s Day gift? One that fulfills the fantasy of having a favorite photograph featured on the cover of National Geographic magazine? This month, National Geographic is publishing a special collector’s edition, National Geographic Your Shot, featuring 101 of the best readers’ photographs submitted to National Geographic magazine over the past three years. Starting Monday, June 15, readers can create and order a unique, customized cover of this special issue, using a photograph of their choice, by going to ngm.com/your-shot-special. The customized version makes a perfect gift to memorialize a special family snapshot.The custom cover option for National Geographic Your Shot will be available to order, online only, for $19.99 plus shipping. The issue goes on newsstands with a standard cover on Tuesday, June 30, for $10.99.The 144-page issue, with a trim size of 7″x7″, also will also contain advertising—from HP, Fuji and Energizer, among others.