Are these pixel art? No. These are "Excel" art.
Mr.Tatsuo Horiuchi, 73-year-old living in Gunma, Japan draws a picture by Excel from 2000.
He is studded with auto-shapes in a worksheet innumerably and gives coloring. It is incredibly delicate that it was described in Excel.
Why will he draw a picture by Excel? He said, "Graphics software were expensive, but Excel was preinstalled in a PC. And it is higher-performance than paint and is easy to use it". He makes friends with oil painters and Japanese painters, and exchanges information now. Furthermore, he runs a Website and shows a method to describe Excel art. Unfortunately it supports only Japanese. However, we can watch his works here.