Code2Flow - An easy solution to create product flows.
PabloDraw - PabloDraw is an Ansi/Ascii text and RIPscrip vector graphic art editor/viewer with multi-user capabilities.
asciiflow - Infinite ASCII diagrams, save to Google Drive, resize, freeform draw, and export straight to text/html.
JavE - JavE (Java Ascii Versatile Editor) is a free Ascii Editor.
Flowchart.js - Draw SVG flow charts from simple text representations of the diagrams.
LaTeXDraw - LaTeXDraw is a graphical drawing editor for LaTeX.