Proxychains is open source software for GNU/Linux systems.
proxychains - a tool that forces any TCP connection made by any given application
to follow through proxy like TOR or any other SOCKS4, SOCKS5 or HTTP(S) proxy.
How to install Tor and Polipo in Backtrack 5 R3
How to Use Tor in Backtrack 5 R3 Whole System Using Proxychains