Recently I had to work around some network filtering systems. One of the tools I use is OpenVPN. What makes OpenVPN great is its flexibility. Either host the server yourself or use one from a third-party VPN provider, of which most support OpenVPN. An issue with having many (third-party) OpenVPN configuration files is that they are not personalized. Sometimes you really need to add some additional options to increase security, but editing many files to allow easy switching of VPN end-points is never fun. There is a solution for this: 'stacked' VPN configurations. One OpenVPN instance can load its configuration from multiple configuration files.