IPv4 forward on windows?

Is there anything that can forward/redirect all incoming traffic to another ip. Basically I'm looking the windows equivalent of ip forwarding in linux.

echo "1" > /proc/sys/net/ipv4/ip_foward 

The direct equivalent is a registry setting. It varies on different versions of Windows but on XP it's:

HKEY_LOCAL_MACHINE \SYSTEM\CurrentControlSet\Services\Tcpip\Parameters\IPEnableRouter

See this list

I wrote an article on Codeproject about redirecting traffic to another address, you specify the source ip address and port, the destination ip address and port and the traffic gets redirected...written in C# .NET.

Hope this helps, Best regards, Tom.