How long has my computer been running? A fundamental question that Unix-y systems can answer with the uptime command.
For some odd reason, Windows 7 has no built-in uptime command. You can simulate this by displaying the date and time Windows 7 last rebooted as reported by the net statistics command. Put this in a file named uptime.bat somewhere on your path:
for /f "tokens=1,2,*" %%i in ('net statistics workstations ^| find "since"') do @echo %COMPUTERNAME% up since %%k
Then open a command prompt and type in the freshly minted command:
MYCOMPUTER up since 5/15/2013 5:21:27 PM