MINCE

MINCE is a text editor for microcomputers that run the CP/M operating system. Developed in BDS C by Mark of the Unicorn, it was bundled with computers from Kaypro and Morrow Designs, and the Epson QX-10. It was a subset of Emacs (MINCE stands for "MINCE Is Not Complete Emacs") designed to run within the 64kB memory limit of 8-bit computers.
MINCE used a gap buffer to fit within 48kB, and implemented a very efficient virtual memory system to support multiple buffers and a maximum file size limited only by available disk space. Although it was not open source, MOTU distributed partial code they deemed most useful for extending the product. MINCE was a companion product to SCRIBBLE, a text formatter based on Scribe. This separation of duties into editor plus formatter was common among advanced word processors at that time.
In 1981 MINCE and SCRIBBLE were sold together, along with their source code and the BDS C compiler, as a software bundle for US$350 (almost US$1000 in 2014 dollars) under the name "Amethyst". Amethyst was available without the compiler for $250, and MINCE and SCRIBBLE were available alone for $175. MINCE and SCRIBBLE were later developed into the Perfect Writer and FinalWord word processors. FinalWord later became Sprint. In 1984 the list price of MINCE was US$175. (equivalent to US$433.22 in 2019)