Three Rings Design, Inc. was an online game developer that was founded on March 30, 2001, by Daniel James and Michael Bayne.

Whirled allowed creators to list virtual goods such as avatars, in-world toys or game content and earn real-world currency from the system.

Three Rings created a number of Flash games for Whirled, notably Corpse Craft, which was later released on iPad.

Spiral Knights is an action-adventure world where players cooperate to defeat the denizens of The Clockworks, a mysterious ever-changing maze.

Shortly after the launch of Puzzle Pirates, Three Rings Design open-sourced substantial parts of the underlying technology for creating multi-user virtual worlds, available on GitHub.