Add-Type @"
using System;
using System.Runtime.InteropServices;
public class User32 {
    [DllImport("user32.dll")]
    public static extern bool GetCursorPos(out POINT lpPoint);
    public struct POINT {
        public int X;
        public int Y;
    }
}
"@

while ($true) {
    $point = New-Object User32+POINT
    [User32]::GetCursorPos([ref]$point)
    Write-Host ("X: {0} Y: {1}" -f $point.X, $point.Y)
    Start-Sleep -Milliseconds 100
    Clear-Host
}