Since studying computer science in the 1970s, Jem Finer has worked in a variety of fields, including photography, film, experimental and popular music, sound recording, sculpture and installation. An enduring fascination with deep time and space, self-organising systems and long-durational processes has been the impetus behind much of his work including his Artangel commission, Longplayer, a thousand-year-long musical composition playing since the last moments of 1999, Cosmolog, a two-year-long artists residency in the astrophysics department of Oxford University, the 2005 PRSF New Music Award winner, Score For a Hole In the Ground, a permanent, self-sustaining musical installation in a forest in Kent, which relies only on gravity and the elements to be audible and and the Gurdy and Hurdy stones, ancient rocks set upright in fields in East Sussex and Gloucestershire with Jimmy Cauty. Their work together includes a band, The Standing Stones, who have released several records on L-13 Light Industrial Recordings.

During his residency in Oxford he started to use the term "post-digital" to describe a change in his modus operandi; a return to a direct relationship with materials and landscape - as opposed to one mediated via a screen - informed by over 30 years of working with computers. The intention was not to disavow digital technology, rather to question its sustainability, to reconsider and reconfigure older technologies and to reconnect with a sense of place. His work there included two sculptural radio-observatories, Landscope, in, and on the shore of, Lough Neagh, N.Ireland and The Centre of the Universe, in University Parks, Oxford, within which he lived a semi-hermetic existence for a month, a vital human presence caretaking, collecting and collating the everyday signals from outer space.

Recent work focuses on these interests and includes Kung Fu Pinball, a pinball machine modified to auto-compose music, Slowplayer, a 3 r.p.m. sound system, Spiegelei, a 360-degree spherical camera obscura and a fascination with the hurdy-gurdy. Supercomputer found Finer's "post-digital" thinking having come full circle in the form of a sculptural machine of a computational process, indebted as much to Jean Tinguely's Métamatics as to John Conway's Game of Life.

In the late autumn of 2021 Sonic Ray transmitted the sound of Longplayer from Trinity Buoy Wharf lighthouse, across the Thames, to Richard Wilson's Slice of Reality, encoded in a laser beam.

Recent music includes the release crowpop and hrdy grdy, an album of hurdy gurdy and minimal electronics, which was released by Thanet Tape Centre in July 2022.

Underground, music for an exhibition of Jock McFadyen's paintings of tube stations, was released in February 2024.

His latest collaboration, with John Matthias, Almost Starlight, will be released by Touch in September 2026.