These are not computer designed but the amazing hand drawn artwork of American Eugene Andolsek. The intensely colourful and intricate works were created by Andolsek starting in the 1950's as a calming pastime. Using a black pen, graph paper, a compass and coloured markers he created piece after piece without even considering them as art. It wasn't until the end of his life that a care worker found his trove of incredible work and brought it to wider attention. Just before his death in 2008 Eugene Andolsek's work was part of an exhibition at the American Folk Art Museum. Over a 60 year period he produced around 2000 works which had never been on display, just hidden away in cupboards and old trunks. He was a truly secret artist.
You can read and view more of his work here.