Question: Harvey Milk is an American experimental rock/noise rock band that formed in Athens, Georgia in the early 1990s, one April Fool's Day gig at the 40 Watt in Athens, they performed R.E.M.'s "Reckoning" album from beginning to end, while which American singer, songwriter, musician, film producer, music video director, visual artist, and philanthropist, was in attendance?

Context articles: Masters of the Hemisphere
Harvey Milk (band)
Michael Stipe
Vietnam (band)
Greed (Swans album)
Swans (band)
Parts &amp; Labor
Jittery Joe's
Janne Westerlund
Oh-OK

Masters of the Hemisphere are an American indie pop group, founded by Bren Mead and Sean Rawls.
 The two moved to Athens, Georgia, to attend college in 1996.
 There they met Ryan Lewis, co-founder of Kindercore Records, who played drums at the first Masters of the Hemisphere show.
 Jeff Griggs (also of The Mendoza Line) soon replaced Lewis.
 In 1997 Kindercore released their debut seven-inch ep, "Going on a Trek to Iceland".
 The group then recorded their first full length album, the eponymous "Masters of the Hemisphere", which was released on Kindercore Records in 1998.
 The band soon expanded to a four-piece, adding multi-instrumentalist Adrian Finch.
 Several singles and compilation appearances followed, including a release on the Happy Happy Birthday To Me Records singles club, before the band released their second full length, the concept album "I Am Not a Freemdoom", also on Kindercore.
 The record garnered mixed reviews, which in part was likely due to the album's rather complicated concept, regarding an island of reservoir-dwelling creatures being enslaved by an evil dog.
 The "Permanent Stranger" EP followed in 2002, on the dcBaltimore2012 label.
 The band split up after their next album, 2002's well received "Protest a Dark Anniversary".
 A recording of their then-final show at Athens, Georgia's 40 Watt Club was later released as "The Last Show Ever".
Harvey Milk is an American experimental rock/noise rock band that formed in Athens, Georgia in the early 1990s.
 While Harvey Milk invariably draws comparisons to the Melvins, due to their penchant for slow, heavy riffs, the band has touched upon such artists as ZZ Top, Led Zeppelin, Leonard Cohen, and Kiss as influences in their music.
 They even went so far as to perform a live show consisting of nothing but Hank Williams covers.
 One April Fool's Day gig at the 40 Watt in Athens, they performed R.E.M.'s "Reckoning" album from beginning to end, while Michael Stipe was in attendance.
John Michael Stipe (born January 4, 1960) is an American singer, songwriter, musician, film producer, music video director, visual artist, and philanthropist.
 He is best known as the lead singer of the alternative rock band R.E.M. from their formation in 1980 until their dissolution in 2011.
Vietnam is a rock, post-punk and new wave band from Atlanta, Georgia on Scared Records.
 Vietnam first appeared at the dawn of a new decade—the 80's, and ushered in a fresh era of music to the Atlanta new wave scene.
 Embraced by the early 80's cavalcade of Athens bands such as R.E.M., Pylon, Method Actors, Love Tractor, etc., Vietnam wowed the patrons of the legendary 688 club, 40 Watt club, and the Agora Ballroom.
 Their first performance was opening for Public Image Ltd. in April 1980, and the next year they played the Noise Fest in New York, appearing on the ZG compilation release of the same name along with Sonic Youth, Glenn Branca, Y Pants and others.
 They released their first full-length album on Scared Records in 2004, "Past Away".
Greed is the third studio album by American experimental rock band Swans.
 It was released in 1986, through record label K.422.
 "Greed" marks the slow turning point for Swans away from the harsh, brutal noise rock of prior releases, and is also the first Swans album to contain contributions from Jarboe.
Swans ( ) are an American experimental rock band formed in 1982 by singer, songwriter and multi-instrumentalist Michael Gira.
 One of few acts to emerge from the New York City-based no wave scene and stay intact into the next decade, Swans have become recognized for a unique, ever-changing sound which has contributed to the development of such genres as noise rock, post-punk, industrial and post-rock.
 Initially, their music was extremely harsh, unprecedented in its sonic brutality and misanthrophic lyrics.
 Following the addition of singer, songwriter and keyboardist Jarboe, who first appeared on the 1986 single "Time Is Money (Bastard)" and debuted as a songwriter on the 1987 album "Children of God", Swans began to incorporate more melody and intricacy into their music.
 Jarboe remained the band's only constant member except Gira and semi-constant guitarist Norman Westberg until their dissolution in 1997.
Parts & Labor was an American experimental rock/noise rock band.
 The group was formed in 2002 by B.J. Warshaw and Dan Friel in Brooklyn, NY.
 Drummer Joe Wong joined the band in 2007.
 Parts & Labor released five albums, two EPs, one split album (with Tyondai Braxton), and numerous 7"s and compilation tracks.
 Their music is influenced by DIY punk, experimental/psychedelic rock, and lo-fi electronic music.
Jittery Joe's is a chain of coffeehouses based in Athens, Georgia.
 In 1994, the first Jittery Joe’s opened in downtown Athens, near the famed 40 Watt Club.
 Open 24 hours a day, they offered fresh coffee roasted in-store.
 There are now five locations in Athens, two in Watkinsville, Georgia, and one each in the Georgia cities of Cartersville, Alpharetta, and Buford.
 There is also a location near the Clemson University campus in Clemson, South Carolina and one in Mercer village across from Mercer University in Macon, Georgia.
 A shop was opened in the University Commons housing complex at Georgia State University, although it only stayed open for a few months before closing.
 Its most recently opened shops were opened in a corner of the LifeSprings Resources bookstore on the campus of Emmanuel College in Franklin Springs, Georgia and in early 2016, downtown Columbia, SC near the University of South Carolina, which also features beer and spirits.
 There was also a short-lived location in downtown Milledgeville, Georgia, located near Georgia College and State University.
Janne Westerlund (born 1973) is a Finnish musician, songwriter and visual artist known from such Finnish groups as Circle (with the band since 2001), Pharaoh Overlord, and Plain Ride.
 His main instrument is guitar but on his solo gigs he plays banjo as well.
 He sings and writes lyrics mainly in English.
 Westerlund's career started in the beginning of the 1990s in a small Finnish city called Hamina when he founded Sweetheart, an experimental noise rock group, with his friends.
 After Sweetheart, he released two albums of "organic electronica" with a trio called Chainsmoker.
Oh-OK was an American musical group from Athens, Georgia formed in 1981 with singer/lyricist Linda Hopper, bassist/vocalist/lyricist Lynda Stipe, and drummer David Pierce.
 Other members later included drummer David McNair and guitarist Matthew Sweet.
 The trio began practicing together at parties in the college community in the spring of 1981.
 Their first club performance break came when Stipe's brother, Michael Stipe of R.E.M., needed a backing band for a show at the 40 Watt Club.