Code2Flow - An easy solution to create product flows.
CodeKeep - Codekeep lets you store and share bits of code and text with other users. Snippets can be organized into folders/labels for instant reuse.
Flowchart.js - Draw SVG flow charts from simple text representations of the diagrams.
CodeMyUI - Handpicked code snippets you can use in your web projects
DIagrams Through Ascii Art - Java command-line tool to convert ASCII diagrams to bitmaps.
Anyfiddle - Build, run and share code in any language from your browser