public/Get-PublicIPv4Address.ps1

function Get-PublicIPv4Address {
    <#
    .SYNOPSIS
    Get current public IPv4 address
    .DESCRIPTION
    Geez. Do I really need to elaborate on this one?
    .PARAMETER (none)
    .EXAMPLE
        Get-PublicIPv4Address
    .LINK
        https://github.com/Skatterbrainz/helium/blob/master/docs/Get-PublicIPv4Address.md
    #>

    $response = Invoke-WebRequest "http://ipconfig.me/ip"
    $pattern = 'id="ip_address">'
    $beginstring = $response.Content.Substring($response.Content.IndexOf($pattern)+16)
    $result = $beginstring.Substring(0, $beginstring.IndexOf("</"))
    $result
}