Angle Audio - Live audio conversations as a service
Twine - Twine is an open-source tool for telling interactive, nonlinear stories.
Noor - Chat like you're in the office together
Ink by Inkle - ink is a popular open source scripting language for branching stories, designed for writers
Orbital - Orbital is an Arcade, Puzzle and Single-player video game created by Bitforge Ltd.
Quest - Quest lets you create sophisticated text-based games, without having to program.