Keeps computer awake all night

coffee.ps1

Add-Type -TypeDefinition @"
using System;
using System.Runtime.InteropServices;

public static class Kernel32 {
    [DllImport("kernel32.dll", CharSet = CharSet.Auto, SetLastError = true)]
    public static extern uint SetThreadExecutionState(uint esFlags);

    public const uint ES_AWAYMODE_REQUIRED = 0x00000040;
    public const uint ES_CONTINUOUS = 0x80000000;
    public const uint ES_DISPLAY_REQUIRED = 0x00000002;
    public const uint ES_SYSTEM_REQUIRED = 0x00000001;
}
"@

[Kernel32]::SetThreadExecutionState([Kernel32]::ES_CONTINUOUS -bor [Kernel32]::ES_SYSTEM_REQUIRED -bor [Kernel32]::ES_DISPLAY_REQUIRED)

# Optional: Keep the script running indefinitely
Write-Host "Script is running to prevent idle/sleep. Press Ctrl+C to stop."
while ($true) {
    # Sleep for a while to avoid excessive CPU usage.
    Start-Sleep -Seconds 60
    # Reset the execution state to keep the system awake.
    [void][Kernel32]::SetThreadExecutionState([Kernel32]::ES_CONTINUOUS -bor [Kernel32]::ES_SYSTEM_REQUIRED -bor [Kernel32]::ES_DISPLAY_REQUIRED)
    date '+%F|%T'
}

As a 1-liner as well for SendKeys():

$wsh = New-Object -ComObject WScript.Shell; while (1) { $wsh.SendKeys('+{F15}'); Start-Sleep -seconds 59; date }