Ambient (desktop environment)

Ambient is a MUI-based desktop environment for MorphOS. Its development was started in 2001 by David Gerber. Its main goals were that it should be fully asynchronous, simple and fast. Ambient remotely resembles Workbench and Directory Opus Magellan trying to mix the best of both worlds.
Features.
Ambient does not strictly follow the Amiga Workbench interface paradigm but there are still many similarities: while programs are called tools, program attributes are called tooltypes, data files are projects and directories are drawers.
Ambient is localized for various languages and while it is part of MorphOS, it is also available separately. There are various visual effects in Ambient which are taking an advantage of hardware accelerated visual effects in MorphOS.
Desktop icons.
The native icon format in Ambient is a PNG icon but there is built-in support for other Amiga icon formats. Ambient introduced special icon format called DataType Icons where the icon is simply any image file renamed to include ".info" extension. Those icons are read using Amiga DataType system.
Development status.
In 2005, David Gerber released Ambient source code under GPL and it is now developed by the Ambient development team.