How do I use GitHub through harsh proxies?

Question

Given the following constraints, how can I use GitHub from Windows and Unix?

• All access to the internet is restricted to a proxy
• The proxy only allows connections out on port 80 and 443
• CONNECT method is only enabled for 443
• Proxy Authentication is required (NTLM or Basic)

Answer 1

See a "Using Github Through Draconian Proxies (Windows And Unix)" by Jeff Tchang, which includes instructions for both Windows and Unix platforms.