I’ve been having a fascinating time playing with IBM Bluemix – it makes it very easy to throw together an Internet-facing application running, say, Java or Node.js together with persistent storage. But the real magic comes with access to Watson APIs (such as Watson Personality Insights) and a whole load of Analytics APIs.
You can see the (enormous) list of the services available with Bluemix by signing up (for free) at https://www.ibm.com/cloud-computing/bluemix/ and then going to https://console.ng.bluemix.net/catalog/
David Barnes’ video at https://www.youtube.com/watch?v=GsGnyZedlFk is also very good (although it’s from February 2016 so slightly out of date).
If you want to learn more about Bluemix try the IBM Bluemix essentials course.
All highly recommended.