I really like the web push notification architecture: you register with the service you want to be notified from (like a chat server or an IRC not) and give them an ID from the push notification server your device listens to.

There’s no extra control outside of the user and the services they want to talk to (I think you can even host your own on Firefox), no vendor lockin, and the power and bandwidth usage are all great. There’s too much money to be made breaking useful push notifications and charging for ads though so I’ll be shocked if it ever gets done right on popular consumer devices.