Sysinternals has feature that allows you quick access to all their free tools. These are some of best diagnostic and troubleshooting utilities available for Windows. Also, Mark Russinovich and his team are continuously updating the existing tools and creating new ones.
You can download any of the utilities without having to unzip them. All you have to do is remember the following URL to download them live.sysinternals.com.
You can also attach live.sysinternals.com like any other network mounted drive, and run the utilities directly from the Internet.