Do you remember Swiss Army Knife? very simple and small tool but great with many features, useful for multipurpose work. That's the way this free tool goes to be...
NetTools is a collection of network scanning, administration tools, system tools and much more with intuitive user interface. Net Tools is mainly written by Microsoft VB6, C+, and C#. It's contain more than 175 tools that you can choose what you need and use from configuration menu.
After you install the program, you can actually copy the executable file(EXE) into your USB disk (don't forget to bring the library files needed!).
So, NetTools is actually a ‘Portable Swiss Army’ Network Toolkits.
Download NetTools 5 here (25MB and require .Net Framework to run)