Get-LastBootTime.ps1

<#
.SYNOPSIS
    Shows when last your PC started up.
.DESCRIPTION
    This is a WMI wrapper function to get the time that your PC last started up.
.PARAMETER ComputerName
    The name of the Computer you want to run the command against.
.EXAMPLE
    Get-LastBootTime -ComputerName localhost
.LINK
    www.howtogeek.com
#>
param(
    [Parameter(Mandatory=$true)][string]$ComputerName
)

Get-WmiObject -Class Win32_OperatingSystem -ComputerName $ComputerName | Select-Object -Property CSName,@{n="Last Booted";e={[Management.ManagementDateTimeConverter]::ToDateTime($_.LastBootUpTime)}}