What are some alternatives?
When comparing asciiflow and Sixteen Colors Draw, you can also consider the following products
Charaster - Open-source ASCII art editor for browser-based, raster-style editing
Playscii - Full-featured ASCII art and graphic editor and game creation tool
Ascii Generator 2 - Ascii Generator 2 (Ascgen2) is an application to convert images into high quality ASCII art - text...
Monodraw - Monodraw allows you to easily create text-based art (like diagrams, layouts, flow charts) and...
ASCII Art Maker - A program for creating ASCII graphics from images and text.
JavE - JavE (Java Ascii Versatile Editor) is a free Ascii Editor.