Suggestions for Plain-widow

The following packages have something in common with the package Plain-widow. The packages are ordered in decreasing similarity.

Package harvmac: Macros for scientific articles
Package resumemac: Plain TeX macros for resumés
Package letter1: Letter formatting macros
Package mlawriter: Write MLA style documents in Plain TeX
Package histyle: A HighStyle environment for TeX
Package automagic: Automatic counter numbering in Plain TeX
Package lextex: Typesetting legal documents using plain TeX
Package lua-widow-control: Automatically remove widows and orphans from any document
Package plain-grid: Four sets of macros for typesetting on a baseline grid
Package ifis-macros: Check if a given input string is a number or dimension for TeX
Package letter-plain: Letter macros for Plain TeX
Package figplace: Floating figures in Plain TeX
Package lettermac: Simple macros for writing letters (Plain TeX)
Package label-pln: Print address labels in three columns
Package toc: Table of contents macros for Plain TeX
Package twoside: Two-side typesetting in Plain TeX
Package toc-zar: Plain TeX table of contents macros
Package font-selection: Font selection for plain TeX
Package font-change: Macros to change text and mathematics fonts in plain TeX
Package hyplain: Basic support for multiple languages in Plain TeX
Package fontch: Changing fonts, sizes and encodings in Plain TeX
Package twocolumns: Knuth’s two-column output macros
Package list: Verbatim listing of text files
Package pdcmac: Damian Cugley’s document tools
Package border: Draw a black border around a Plain TeX page
Package cropmrks: Add crop marks to a Plain TeX document
Package firstline: Print the first line of a paragraph in a different font
Package placeins-plain: Insertions that keep their place
Package varindent: Make paragraph indentation match the length of the line above
Package eplain: Extended plain TeX macros
Package graphics-pln: LaTeX-style graphics for Plain TeX users