One of the things that is often handy to know is when a server was last rebooted. This is nice to know for things like patching, registry updates, etc… stuff that requires a reboot to take affect.
I came across a quick article that explains a very quick way to get an answer.
Open up a command prompt and use the following command:
systeminfo | find "Time:"
A few seconds later you will get a response telling you when the last system boot was. Very handy!