Question: Which of the following bands is a side project of John Flansburgh, one of the founding members of They Might Be Giants: Mono Puff or Sum 41?
Context: The following is a comprehensive discography of They Might Be Giants, an American alternative rock band comprising several artists including John Flansburgh, John Linnell, Marty Beller, Dan Miller, and Danny Weinkauf.  The band's first release was the November 4, 1986 eponymously titled "They Might Be Giants", but TMBG did not gain commercial success until their March 1990 single "Birdhouse in Your Soul" from the album "Flood".  "Birdhouse in Your Soul" reached #3 on the United States Modern Rock Tracks chart and #6 on the UK Singles Chart and remains their highest-charting single in both countries.  Over the next two decades, They Might Be Giants released studio albums on a near-biennial fashion and currently have a total of 19 studio albums along with six live albums, eight compilation albums, 21 extended plays and 11 singles. Sum 41 is a Canadian rock band from Ajax, Ontario.  Originally called Kaspir, the band formed in 1996 and currently consists of lead vocalist/rhythm guitarist/keyboardist Deryck Whibley, lead guitarist/backing vocalist Dave Baksh, rhythm/lead guitarist/keyboardist/backing vocalist Tom Thacker, bassist/backing vocalist Jason McCaslin and drummer Frank Zummo. Direct from Brooklyn is a compilation of music videos by American alternative rock group They Might Be Giants.  It was released on VHS in 1999 and DVD in 2003.  The title refers to the home of John Linnell and John Flansburgh, founding members of the band.  Many of the music videos were filmed in Brooklyn and other parts of New York City. They Might Be Giants In...Holidayland (sometimes referred to simply as Holidayland), was a holiday-themed E. P. released by the band They Might Be Giants in 2001 (see 2001 in music) under Restless Records.   The recording consists of: "Santa Claus", a Sonics cover originally released on Emusic.com's TMBG Unlimited service; "Santa's Beard", first released on "Lincoln" and later ""; "Feast of Lights", also from TMBG Unlimited, and appearing on the compilation "Festival of Lights 2"; "Careless Santa", from Mono Puff's album "Unsupervised"; and "O Tannenbaum", from 1993's "O Tannenbaum" E. P. and, later, TMBG Unlimited. Dial-A-Song: 20 Years Of They Might Be Giants is a 2002 compilation album by They Might Be Giants issued by Rhino Records and compiled by singer, songwriter, and guitarist John Flansburgh.  Despite its name, the compilation does not include tracks from the band's "Dial-A-Song" service.  It is instead an anthology of various album and live tracks from the band's history, spanning their full career up to the time of its release.  It includes tracks from every album starting with 1986's "They Might Be Giants" up through "No! ", their first children's album, which was released only three months before this compilation. People Are Wrong is a 2004 Off-Broadway musical written by Robin Goldwasser and Julia Greenberg, and stars John Flansburgh, Robin Goldwasser's husband, from the band They Might Be Giants.  It played Off-Broadway at the Vineyard Theatre from October 22, 2004 until December 11, 2004.  The production starred John Flansburgh, Erin Hill, David Driver, Robin Goldwasser, Chris Anderson and Maggie Moore. Mono Puff is a New York City-based band and a side project of John Flansburgh, one of the founding members of They Might Be Giants. Robin Goldwasser (born August 14, 1966) is an American singer and playwright.  She is a graduate of Sarah Lawrence College.  She is the co-writer of the musical "People Are Wrong! " with Julia Greenberg.  She has a character in the play, as does the producer, her husband, John Flansburgh of They Might Be Giants and Mono Puff.  The musical opened at the Vineyard Theater in New York in November 2004, starring Robin, John Flansburgh, Erin Hill, David Driver, and Maggie Moore. Dan Miller (born October 3, 1967) is an American musician and songwriter.  He has toured and recorded with the alternative rock duo They Might Be Giants since late 1998.  Generally, Miller plays guitars for the band.  Prior to joining TMBG, he performed with the groups Edith O and Lincoln.  Having left Lincoln for personal reasons in 1998, he was contacted by John Flansburgh, who offered him a spot as lead guitarist for They Might Be Giants' Fall 1998 tour.  He has also toured with John Flansburgh as Mono Puff's guitarist in the late 1990s, and played on bandmate John Linnell's "State Songs" tour. Danny Weinkauf (born December 4, 1963) is a Grammy-winning New York-based musician and composer.  He has been the longtime bassist for They Might Be Giants (TMBG).  He has recorded and toured with the band since the late 1990s.  Weinkauf had previously performed in a band called Lincoln along with TMBG's guitarist Dan Miller and drummer Gonzalo Martinez De La Cotera.  He has written four songs for TMBG, all for their children's albums.  Weinkauf wrote and sang "Where Do They Make Balloons?"  on the children's album "No! ", "Number Two" from "Here Come The 123s", "I Am a Paleontologist" from "Here Comes Science", and "Elephants" from "Why? " He also played bass alongside bandmate John Flansburgh for his solo project Mono Puff, in addition to providing additional bass on John Linnell's "State Songs" album.
Answer: Mono Puff