ViewHTTPHeaders.com - View HTTP header response for any web page.
socat - socat is a relay for bidirectional data transfer between two independent data channels.
HTTP Header Live - Displays the HTTP header. Edit it and send it.
Komodia Relay - Free open source tool to perform TCP based session relay
RequestHeaders.com - HTTP Header Checker Tools
PortMapper - Do you need to map a specific TCP or UDP port on your machine to another port on another machine?