Mpage is a program to reduce and print multiple pages of plain text
per sheet, such as 1, 2, 4, or 8 pages on one sheet.  Pages are
tiled and separated by lines.

It also has limited functionality to do the same with Postscript
files itself.

A Postscript printer or a Postscript interpreter (such as ghostscript)
is required.

Mpage can be used to convert plain text to Postscript.