WizTree - WizTree quickly finds the files and folders using the most space on your hard drive. It scans the MFT (Master File Table) instead of crawling the entire disk which makes it very fast.
Pathman - A Windows platform tool that edit PATH enviroment variable(both system wide and user wide)
TeraCopy - TeraCopy is a compact program designed to copy and move files at the maximum possible speed, providing the user with a lot of features.
eveditor - Your trusty environment variables editor
Process Hacker - Process Hacker is a feature-packed tool for manipulating processes and services on your computer.
Path-Manager - Download Path-Manager for free.