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Recently, I only came to appreciate the power and beauty of VPN. I've long associated VPN only with "being able to access office resources and email while at home", but the technical beauty of it, is that it allows you to securely connect to an internal/private network from outside of that network.
The power of VPN is that the entire lot of of my internal LAN-only services is instantly made available to me, *as though I were at home connected to my LAN*. No messy reverse proxy configs or endless port mappings. The only port that needs exposure is a single UDP port for the VPN service. It's also great for stuff like Moonlight (game streaming) where ports can be finnicky. And I can code from anywhere because my dev server is accessible via VPN.
Once connected, I have access to all my services. Incredible stuff.