Kitchen Motors' aesthetic, which focuses on largely improvised and electronic music, also applies to his other projects. Apparat Organ Quartet, with music described as "machine rock & roll," consists of four keyboardists who play discarded vintage instruments that they refurbish and a drummer. Jóhannsson's work on his own ranges from delicate laptop pop to sound art installations in galleries to collaborations with Barry Adamson, the Hafler Trio, and Pan Sonic. His first solo album, 2002's Englabörn, paired a string quartet with percussion, keyboards, and electronics in a series of bittersweet miniatures, while 2004's Virthulegu Forsetar was a much more expansive work scored for brass, organ, keyboards, and electronics that was composed for and recorded in Reykjavik's Hallgrimskirkja Church. The British label Touch released both of these albums, but 2005's Dis was issued by Worker's Institute.

For 2006's IBM 1401, A User's Manual, Jóhannsson moved to 4AD. One of Jóhannsson's most ambitious projects, it was inspired by the first computer brought to Iceland in 1964 and based on a recording of an IBM computer that his father made on a reel-to-reel tape recorder. A string quartet version of the work was performed as the accompaniment to a dance piece by choreographer Erna Omarsdórtir at the 2002 Dansem Festival. The recorded version of IBM 1401, A User's Manual incorporated vocalizing, electronics, and a 60-piece orchestra along with the original recordings of the IBM computer. Released in 2008, Fordlandia, inspired in part by Henry Ford's failed rubber plant in Brazil, was the second part of a planned trilogy about technology and iconic American brands. Jóhannsson toured the U.S. in summer 2009, and the soundtrack he composed for the animated film Varmints was sold as And in the Endless Pause There Came the Sound of Bees, a limited-edition, tour-only release. The album was given a wider release the following year on Type.

Two years later, Jóhannsson's music for Bill Morrison's documentary The Miner's Hymns arrived on FatCat; during the early and mid-2010s, he composed the scores to many films, including 2012's Copenhagen Dreams, 2013's Prisoners, 2014's The Theory of Everything (which won him a Golden Globe and an Oscar nomination for Original Score), and 2015's Sicario, which also earned a Best Original Score nomination. In 2016, Jóhannsson's collaborative score with Hildur Gudnadóttir for the BBC TV series Trapped won the Best Score award at that year's Edda Awards in his native Iceland; that year, the composer also signed with Deutsche Grammophon to release some of his non-score projects. The first of these was Orphée, his first solo studio album in six years. Inspired by several versions of the Orpheus myth -- including French director Jean Cocteau's film -- as well as Jóhannsson's move to Berlin, Orphée arrived in September 2016. His film music was still a priority, with his score to Denis Villeneuve's Blade Runner sequel scheduled for release in 2017. His third collaboration with Villeneuve was released in late 2016, having composed the score for his sci-fi thriller Arrival. ~ Heather Phares