Cntlm is an NTLM / NTLMv2 authenticating HTTP/1.1 proxy. It caches auth'd connections for reuse, offers TCP/IP tunneling (port forwarding) thru parent proxy and much much more. It's in C, very fast and resource-efficient. Go to http://cntlm.sf.net/
OpenVPN 2 is a robust and highly flexible tunneling application that uses all of the encryption, authentication, and certification features of the OpenSSL library to securely tunnel IP networks over a single TCP/UDP port.
Discussion forums and project wiki can be found here:
https://forums.openvpn.net/
https://community.openvpn.net/