Is it possible to set base font-size to <10 as in newspapers.
Here is sample code
\documentclass[9pts]{article}
\usepackage{lipsum}
\begin{document}
\lipsum
\end{document}
If you are choosing scrartcl
, instead of article
you could do that.
\documentclass[9pt]{scrartcl}
\usepackage{lipsum}
\begin{document}
\lipsum[1-5]
\end{document}
You have a few options,
Use another document class, such as Koma-script as in @Jan's answer
If you want to stick to the standard class, you can define your own \normalsize
etc.
A minimal example is,
\def\normalsize{\@setfontsize\normalsize{9}{11pt}}
In standard class' definition of \normalsize
there are other stuff, such as display skips, etc. You would probably like to redefine \small
etc similar.