Apple Panic/Versions

Atari 400/800
Olaf Lubeck, who also authored Frogger, programmed the Atari 400/800 port.

IBM PC-DOS
Supposedly the IBM PC-DOS version was also authored by Olaf Lubeck, who did the Atari port.

Seed7
A port was made many years later in the open source programming language, Seed7.

TRS-80
A version for the TRS-80 family exists that was written in 1982 by Yves Lempereur of Funsoft, Inc.