This is a JavaScript DCPU16 emulator implementation.

It implements the v1.7 spec, and the following devices:

• LEM 1802 monitor
• Generic keyboard
• Generic clock
• HMD2043 floppy drive (not Notch's, but he said he'll use that spec verbatim or nearly so).
• a non-standard in-circuit debugger

The emulator may be used online here: http://www.toothycat.net/~sham/dcpu16
A MoonOS build is also available online: http://www.toothycat.net/~sham/dcpu16/index.html?shell=asm%20kernel.dasm16

The version of the emulator and MoonOS on the site may lag behind GitHub by as much as a day.
A wiki page is located here: http://www.toothycat.net/wiki/wiki.pl?MoonShadow/DCPU16
The author may be contacted via this.