twoside – Two-side typesetting in Plain TeX
Defines macros that produce output destined for two-sided printing, with a gutter margin as specified by the user. A running head may also be specified.
Maybe you are interested in the following packages as well.
- fixpdfmag: Fix magnification in pdfTeX
- harvmac: Macros for scientific articles
- letter1: Letter formatting macros
- lextex: Typesetting legal documents using plain TeX