Paessler Netflow Tester 

Paessler Netflow Tester is a free program that simply dumps the data of all Netflow packets that a computer receives from a Cisco router. This can be useful when debugging bandwidth monitoring configurations based on Cisco's Netflow protocol.
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Advanced TCP Logger 

This program is a simple proxy server(port-mapper). It is an ideal tool for monitoring any network software or for researching network protocols.
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Proxy Workbench 

Proxy Workbench is a unique proxy server ideal for developers, trainers and security experts that displays its data in real-time.
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