Suggestions for mparhack
The following packages have something in common with the package mparhack. The packages are ordered in decreasing similarity.
- marginal: Extensions to \marginpar handling
 - marginfit: Improved margin notes
 - snotez: Typeset notes, in the margin
 - mnotes: Margin annotation for collaborative writing
 - marginfix: Patch \marginpar to avoid overfull margins
 - sidenotes: Typeset notes containing rich content, in the margin
 - flexipage: Flexible page geometry with marginalia
 - sidenotesplus: Place referenced notes, alerts, figures and tables into the document margin
 - margbib: Display bibitem tags in the margins
 - pdfreview: Annotate PDF files with margin notes
 - zebra-goodies: A collection of handy macros for paper writing
 - marginalia: Non-floating marginal content with automatic placement for LuaLaTeX
 - was: A collection of small packages by Walter Schmidt
 - upgreek: Upright Greek letters
 - url: Verbatim with URL-sensitive line breaks
 - texments: Using the Pygments highlighter in LaTeX
 - nath: Natural mathematics notation
 - prosper: LaTeX class for high quality slides
 - subfloat: Sub-numbering for figures and tables
 - alnumsec: Alphanumeric section numbering
 - sudoku: Create sudoku grids
 - morehype: Hypertext tools for use with LaTeX
 - brclc: Support 16-bit (double) calculations in LaTeX
 - nicetext: Minimal markup for simple text (Wikipedia style) and documentation
 - handout: Create handout for auditors of a talk
 - balance: Balanced two-column mode
 - sciposter: Make posters of ISO A3 size and larger
 - bondgraph: Create bond graph figures in LaTeX documents
 - easyformat: Easily add boldface, italics and smallcaps
 - aguplus: Styles for American Geophysical Union
 - anysize: A simple package to set up document margins