He created the games Manic Miner and Jet Set Willy for the ZX Spectrum, released in 1983 and 1984 respectively.

[4] He obtained a ZX Spectrum on loan from Bug-Byte Software Ltd. in return for a freelance contract for three games.

Smith has stated that Manic Miner was the most enjoyable game to make for him whereas Jet Set Willy was 'seven shades of hell'.

Unlike his previous two hits The Mega Tree was not developed for the ZX Spectrum but the Commodore 64.

He lived in a Dutch commune from around 1995 but was deported from the Netherlands in October 1997 and returned to Britain, saying that he had failed to keep his residency papers in order.

In 2000, he appeared on a British television documentary programme called Thumb Candy about the history of video games[13] in which, in a brief interview, he discussed Manic Miner and his 1980's career.