For many years one of my favorite utilities has been the incredibly brilliant and tiny MS Uptime.exe. It will give the current uptime of either LM, or any machine on the network. It will also dump the event logs (local or remote) of all the shutdown/reboot/BSOD & boot events which made creating a (up)timeline a snap for troubleshooting.
But... It was written back in 1999, and is (for whatever reason) no longer reliable. It tends to crash when trying to get a list of when/why the (local or remote) machine was rebooted.
Here is a sample of it output (run locally):
Lacking the time to scratch write it myself, I was hoping someone knew of a comparable alternative that was currently available (that works). CLI is preferable, but I'll suffer through a GUI if I have to.