FlowMapp - FlowMapp is a UX planning tool for creating visual sitemaps and user flow.
State.of.dev - Visualizing the current state of development
Octopus.do - Build your website structure in real-time and rapidly share it to collaborate with your team or clients. Start prototyping websites or apps instantly.
Algorithm Visualizer - Write down your algorithm to be visualized
DYNO Mapper - Create Sitemaps with the DYNO Mapper Visual Sitemap Generator.
A1 Sitemap Generator - A1 Sitemap Generator has been in active development and sold since 2005.