First things first, props to the original script, with updates found here: Original Script by jgamblin
This is a script that will run in a Terminal or iTerm window.
It will monitor your Spotify currently playing song and update your Slack status with it.

Required - Spotify
Create a file in your Home directory called .slacktoken.cfg You need to get a Legacy Token from here
This file needs to have the following text:

SLACK_TOKEN="Your Token Here"

This prevents your token from being in the same location as your script.
One note that I recently discovered. The emoticon that is in the code has to match one that you have in your Slack instance. Otherwise it won't work.

Download the bash file:

slack_status.sh

Run it and voila!

Required - iTerm2 unless you edit the file
I wanted to have an app that loaded the bash file in iTerm2 and then launched Spotify.
I have uploaded the Automator file, of which you can edit in order to run in Terminal if you wish.

Spotify-Script.app.zip

Download that, along with the slack_status.sh file.
Make sure you have the config file set correctly.
The app will attempt to open iTem, run the script, and then launch Spotify.