Try KM-Z80 web ver 1.0
Try a game (Bug-Fire) by KM-Z80 web ver 0.8.
Help
Download ver 1.0
Most of source codes (including Z80 emulator by JavaScript) are provided under LGPL license.
Some files are not LGPL, but are free-software.
(ver 1.1)
(ver 0.9)