Using the Pushover.net service, it's easy to script push notifications into your BASH scripts, cronjobs, or any of countless existing application integrations. It's easy to set up, very responsive, and has a single time, $5 fee per platform.
Pushover already integrates with countless services:
https://pushover.net/apps
But in this video I'll show you how to make a simple BASH script send notifications to all your devices. I use Pushover myself, and have zero regrets!
Pushover Website: https://pushover.net
My Push Client Github Page: https://snar.co/pushover
UPDATE: After I posted this, my friend and coworker Knox ( / dataknox ) made a thing: https://github.com/DataKnox/pypusher
Yay open source! :D