Network Manager is a free and open source Windows tool that will aid you in monitoring and configuring your network adapters. It's main features are:
It's compatible with Windows XP-SP3/2003/Vista/2008/7/8 both 32 and 64 bit versions, but load balancing feature works only on Windows 7 and above. Also there is no IPv6 support at the moment.
This program was created with AutoHotkey tool and the help of it's amazing community. It is released under GNU GPL v3 license, and you are free to inspire from it's source code, available below.
If you have any problems using this tool, check the tutorials below or ask it on the forum. Also, you are more than welcome, to post any bugs or suggestions on the forum.
Check this tutorials to see what you can do with Network Manager tool: