Zany80 is a fantasy console designed around the Z80 processor.
Update: 0.2.2 released, 9/26/20.
Zany80 is free software, available under the GPLv3. The source is publicly accessible on SourceHut. Contributions are welcomed and hugely appreciated.
Zany80 was originally called Zenith80, but the name was charged after the discovery that a company called Zenith Data Systems existed that worked with the Z80 processor so as to avoid confusion (and, admittedly, while Zenith is a fun word, Zany80 just has a better ring to it).