SoftEther VPN ("SoftEther" means "Software Ethernet") is one of the world's most powerful and easy-to-use multi-protocol VPN software. It runs on Windows, Linux, Mac, FreeBSD and Solaris.

SoftEther VPN is freeware. You can use SoftEther for any personal or commercial use for free of charge.

SoftEther VPN is an optimum alternative to OpenVPN and Microsoft's VPN servers. SoftEther VPN has a clone-function of OpenVPN Server. You can integrate from OpenVPN to SoftEther VPN smoothly. SoftEther VPN is faster than OpenVPN. SoftEther VPN also supports Microsoft SSTP VPN for Windows Vista / 7 / 8. No more need to pay expensive Windows Server license-fee for Remote-Access VPN function.
Link


This looks like a good alternative to OpenVPN if you plan on assembling your own virtual private network. Intercompatible, better throughput, and punches through firewalls and NAT (ICMP and DNS tunneling is also available; useful for airports and cafes where you have to pay for access but can resolve names and make pings).