It is a package of tools which can help you in system diagnostic and management. Although most of the tools in the Sysinternals suite will never be used by a normal user, some of them can be used by anybody and can greatly enhance your productivity.
I'll start with my favourite, "Desktops". You might have seen people on Linux and Mac using multiple desktops. Desktops gives you upto four desktops on you Windows PC (see image). You may want to use it if you have seen a scroll bar on your Windows taskbar (which nobody I know has ever seen. Try opening 20 windows simultaneously).
Another good one is "procexp". Self Explanatory, it is a process manager for XP. Don't know if it will work in Vista and 7. XP's default Task Manager is real shit. It doesn't even tell you the path of the process it is referring to. Procexp comes to your rescue here. To have a peek at its full power, try right clicking a process and selecting properties. The window will say the rest.
Want to do an autopsy of your virtual memory? Try vmmap.
TCPView also comes handy when you want to see all the processes that are connected to the network. May come in handy for catching Trojans as well.
Well, this is not meant to be a documentation of all of them. Learn as you Explore.
There are lots more (around 40 as of today) in the suite. And its just a 12MB download. Download it here.
