理世X智乃 by 迴旋踢. Original ANSI + Google-translated.
An obscure little program in German to convert images into text, using the words of your choice. It seems to be called RUTVIEW and you can download it here.
Naked PETSCII bouncings by Max Capacity, 2011.
Good shading in this ASCII-conversion by Loxosceles in 2001.
Pepe Trump, posted by noc33 on reddit.
In the 1960s, Eduardo Joselevich and Fanny Fingerman developed a technique to represent images with only four symbols. Full blocks or circles, in either black or white. They called it Fototrama and it was used at Olivetti and Philips for example.
More here.