Arnold/MacOS is an Amstrad CPC/CPC+ Emulator for the Macintosh.
Arnold features emulation for the five different models of Amstrad CPC - namely the CPC464, CPC664, CPC6128, 464 Plus, and 6128 Plus. Arnold features extremely precise emulation, allowing complicated demos to run correctly in emulation. To that end, it runs in 16-bit colour so that the palette can remain 100% accurate. (The CPC+ hardware could support more than 256 different colours on screen at a time). Unfortunately, this means that Arnold is rather slow - my G3/350 can get full speed, but only just. Fortunately Arnold provides a frameskip command, which means you should get full speed (at the expense of smooth graphics) on any G3.
 
Arnold was initially developed by Kevin Thacker for Windows, although now ports are under development for assorted platforms. Kevin also updates Arnold on a regular basis, and I fully intend to keep the Macintosh version in sync with the Windows release. The source code for Arnold is not available to the public.