Unless I've been under a rock, I still don't see a way to have Alexa speak unsolicited. I need to be able to give her a string to speak on demand. I'm using Alexa as a bridge along with IFTTT and an automation system and I am trying to get her to speak events as they are collected and parsed from my automation system. I see the new simon says skill, which is part way there. What else can be done?
This has been called "push notification" and is the #1 most requested feature. You can find the feature quest thread and add your +1 to it if you like. Personally I do not think Amazon will ever implement this due to privacy and liability concerns.
Very sad indeed. Everyone wants a way to push notifications. I do 'fake myself out' by using it as a bluetooth speaker for my computer and send notifications through it. Nothing special about a computer sending audio to a bluetooth speaker, but it works for my use.