2000s. These included Curse Of The Seven Jackals (with Laura Carter, Eric Harris, Chris Jolly & Heather McIntosh), Major Organ and the Adding Machine (with Julian Koster, Kevin Barnes and Will Hart, amongst others), Circulatory System's self-titled debut, Signal Morning and Mosaics Within Mosaics, the Apples in Stereo's New Magnetic Wonder, the Music Tapes' Mary's Voice and Jeremy Barnes' A Hawk and a Hacksaw. Return to live performances In August 2005, Mangum appeared onstage with the Olivia Tremor Control at New York City's Bowery Ballroom to sing "I Have Been Floated". He made no further public appearances until October 2008, when he took part in the Elephant 6 Holiday Surprise reunion tour, performing the Neutral Milk Hotel song "Engine" at several shows accompanied by Julian Koster on singing saw. In December 2009, Mangum contributed a cover of "Sign the Dotted Line" to a Chris Knox tribute album titled Stroke: Songs for Chris Knox. This was followed by an appearance at a Knox benefit show on May 6, 2010 at Le Poisson Rouge, where Mangum performed a number of acoustic Neutral Milk Hotel songs. On December 4, 2010, Mangum played an unannounced set at a loft in Bushwick, Brooklyn. On April 20, 2011, Robert Schneider debuted a score composed by Mangum for the Teletron, a mind-controlled electronic instrument invented by Schneider. In August 2011, Mangum launched the website Walking Wall of Words, through which he self-released a vinyl box set of Neutral Milk Hotel recordings and previously unreleased material. He also curated a series of downloadable 'radio broadcasts' and sold one-of-a-kind drawings, with a portion of proceeds donated to charities including Children of the Blue Sky. Also in August, Mangum commenced a tour of the East Coast, performing mainly Neutral Milk Hotel songs. On September 30, he played a full set at the All Tomorrow's Parties festival in Asbury Park, NJ. On October 4, he made an appearance at Zuccotti Park in New York City and played several songs to those participating in the Occupy Wall Street protests. In March 2012, he curated the ATP festival in Minehead, England, inviting a number of Elephant 6 groups including The Apples In Stereo, The Music Tapes, Olivia Tremor Control and A Hawk and a Hacksaw. Influential artists such as The Fall, Thurston Moore, Roscoe Mitchell and the Sun Ra Arkestra also performed at the three-day event. Mangum's solo tour continued throughout 2012 and