Z64K Beta (2017/09/30) is released. Pixel exact emulation of the Commodore 64, VIC 20 and Atari 2600 written entirely in Java. The emulators should run on any platform with an updated java runtime environment installed.

Z64K Beta Changelog:
1 October - Change Log and New UI
Archived change log into changelog.doc
I've uploaded an updated version of the new UI (see below). It's getting much closer to be able to totally replace the currently released emulators! :)
30 September - C64 BETA
Set raster to correct value when loading snapshots. Fixes loading of snapshots that rely on exact raster position. eg IK+. I discovered bug while implementing snapshots for new UI. See below for link to new UI.

Download: C128 Beta (2017/09/17)
Download: C64 Beta (2017/09/30)
Download: VIC20 Beta (2017/09/17)
Download: Atari2600 Beta (2017/09/17)
Source:Here