Multiple slides on one side in one pdf

Ever had multiple slide sets, e.g. from a lecture, and you needed an overview to print out? With LaTeX that's easy:

\documentclass[a4paper,12pt,landscape]{article}
 
\usepackage{pdfpages}
 
\begin{document}
  \includepdf[offset=5mm 0, nup=4x4, pages={3,4,5,6}]{slide-set-1.pdf}
  \includepdf[offset=5mm 0, nup=4x4, pages={2,10,20,42}]{slide-set-2.pdf}
\end{document}

Now just compile this using pdflatex and you have a single pdf with a nice overview.