Question: What do Hugo Ferreira and Damian Kulash have in common?

Context paragraphs:
Incorruptible Heart: Incorruptible Heart is the second full-length album by the Los Angeles-based band Lavender Diamond, released in September 2012 as a vinyl LP, compact disc and digital download.  250 copies of the LP were pressed on lavender vinyl, with 50 copies packaged in a tote bag with an original drawing by the band's drummer and artist Ron Regé Jr. The album was produced by Damian Kulash of the band OK Go, who also sang backing vocals on one song.

Hugo Ferreira: Hugo Ferreira (born March 7, 1974) is a Portuguese-American African-born singer/songwriter musician.  He is best known for being the lead singer and songwriter for the American rock band Tantric.

The End Begins: The End Begins is the third studio album from American band Tantric.  It is the first one recorded without the band's original members Todd Whitener, Matt Taul, and Jesse Vest.  Vocalist Hugo Ferreira, the only remaining original member, was forced to scrap the original line-up's complete third album in favor of "The End Begins", an effort established by new members of the band in addition to Ferreira.  This is the only studio album to feature former Fuel drummer Kevin Miller.

8in8: 8in8 is a supergroup comprising Ben Folds, Amanda Palmer, Neil Gaiman, and Damian Kulash of OK Go.  In 2011 they gathered together with the intention of writing and recording eight songs in eight hours, hence the name "8in8".  Aside from being friends, members of the group have various connections with each other: Neil Gaiman and Amanda Palmer are married, and Ben Folds appeared on and produced Palmer's solo debut "Who Killed Amanda Palmer".  The band have been referred to as a supergroup, acknowledging that moniker by describing themselves as "tomorrow's supergroup today".  The musical members of 8in8 each have different styles and the EP "Nighty Night" was created to reflect each one, with main lyricist Gaiman adapting to suit.

Damian Kulash: Damian Joseph Kulash Jr. (born October 7, 1975) is the lead singer and guitarist for the rock band OK Go.  He is also a music video director.  He is married to Kristin Gore.

Paul Collins (American writer): Paul Collins (born January 12, 1969) is an American writer, editor and Chair of English at Portland State University, in Portland, Oregon.  He is best known for his work with McSweeney's and "The Believer", as editor of the Collins Library imprint for McSweeney's Books, and for his appearances on National Public Radio's "Weekend Edition Saturday" with Scott Simon.  His own books deal primarily with quirky forgotten figures from history, sometimes interwoven with memoir.  Damian Kulash of the band OK Go has stated that the chapter in Collins' book "Banvard's Folly" about Augustus Pleasonton's patent on blue light led to them naming their third album "Of the Blue Colour of the Sky".

Nighty Night (EP): Nighty Night is an album by 8in8, a supergroup featuring Ben Folds, Amanda Palmer, Neil Gaiman, and Damian Kulash of OK Go.  It was released in April 2011

Tantric (band): Tantric is an American rock band from Louisville, Kentucky, United States.  The group was founded in 1999 by former Days of the New members Todd Whitener, Jesse Vest and Matt Taul (now all no longer with the band), and Hugo Ferreira.  Altogether Tantric has released six studio albums and one EP "Tantric" (2001), "After We Go" (2004), "The End Begins" (2008), "Broken Down...Live in the Poconos" (2008), "Mind Control" (2009), "37 Channels" (2013) and "Blue Room Archives" (2014)

Paracadute: Paracadute is a record company owned by OK Go.  OK Go left their previous record company, EMI, because of a disagreement between the band and the label.  OK Go reissued their album, Of the Blue Colour of the Sky, with Paracadute taking care of the promotion and distribution of the album reissues.  OK Go's lead singer, Damian Kulash, announced the new label in a video posted to the band's YouTube channel.

OK Go: OK Go is an American rock band originally from Chicago, Illinois, now based in Los Angeles, California.  The band is composed of Damian Kulash (lead vocals, guitar), Tim Nordwind (bass guitar and vocals), Dan Konopka (drums and percussion) and Andy Ross (guitar, keyboards and vocals), who joined them in 2005, replacing Andy Duncan.  The band is known for its often quirky and elaborate one-take music videos.

Supporting paragraphs: Hugo Ferreira Damian Kulash
Answer: singer