A client that I'm consulting was being ripped off by a local IT provider with pricing for on-premises servers & MS software. I proceeded to rent cheaper equivalent machines off-site. The IT provider claimed the hardware firewall (Fortigate) was not configurable for site-to-site to the new machines directly (could be, not an expert on those). Therefore, I ended up purchasing several Raspberries and configuring them as OpenVPN routers that opened up the office LAN to said machines. Quite satisfying, as it allowed to break the client out of the proprietry software/hardware/vendor chain at a rather small expense.