Over a decade I set up, updated and periodically managed the IT and software infrastructure of TECTRA Ltd from afar.
TECTRA Ltd is one of the first (possibly, the first) non-IT SME in Greece that adopted open-source software solutions for its internal systems such as email serving (with dovecot) and file sharing (with Samba), and for working with documents, saving money, time and hassle by switching away from Microsoft Office and Outlook to OpenOffice/LibreOffice and Thunderbird.
Additionally, as early as 2002, these services were self-hosted on-premises on a series of commodity PCs (with Pentium II, III, 4, Celeron CPUs) running Linux (SuSE, Slackware, Ubuntu and, since 2008, solely Debian/stable).
A paragraph about what you are working on is enough to start.