Tunnelblick - free software for OpenVPN on OS X and macOS
PuTTY - Popular free terminal application. Mostly used as an SSH client.
OpenVPN - OpenVPN - The Open Source VPN
MobaXterm - Enhanced terminal for Windows with X11 server, tabbed SSH client, network tools and much more
WireGuard - Fast, Modern, Secure VPN Tunnel
iTerm2 - A terminal emulator for macOS that does amazing things.