PowerShell: Check computer last logon date

In a recently closed ticket, I had specified that the solution would be automatically applied upon reboot of a computer. As so often happens one of the twenty or so users affected by the solution emailed to say that it didn’t work. Having dealt with said user before, I had a hunch that they hadn’t actually read the solution text, and wanted to see if I could find out when the computer had last been rebooted.