Since the early 1990s, Helliwell has completed over 100 short experimental films exploring various themes, including sound visualisation, hand-painting, abstraction, animation, video feedback, found footage, and collage. Particularly concerned with fusing his own specially composed electronic music with video and film, he has created one of the largest bodies of experimental shorts in the world to feature electronic music soundtracks by one artist. All his short films feature his own electronic sound, and occasionally he has been commissioned to make music for specific projects – his Brighton Marina time-lapse soundtrack was composed in 2010 for Peacock and McClave's series of 3D shorts.

Helliwell has pursued a creative approach to the research, collection and presentation of archive music, film and art from the early post-war era. He has assembled special film and radio programmes, created new electronic music for old silent films, and written articles for The Wire magazine about the discoveries he has made. Since the start of the 1990s, Helliwell has also been developing his own 'intuitive electronics' method via 'creative soldering', and has built a whole series of Hellitron tone generators, which he uses to realise his film soundtracks. He has also put together more sophisticated synth units - the Hellisizer series - which includes the 1000, 2000, 3000, 4000, Compact and Junior models.