Par is a text formatter written by Adam M. Costello.
I use it with vim.
In the past, I've gone to Adam's site and downloaded par, building it manually.
Here I've collected a patch that supplies autoconf functionality by Nelson H. F. Beebee
as well as a patch by Jérôme Pouiller that handles multibyte characters.
I haven't added any new functionality, this is just a matter of convenience for me.
You do the standard ./configure; make; make install dance.