Here you’ll find a couple of videos from Microsoft about the new Cortana Analytics Suite (which combines Azure ML with Power BI and Cortana speech recognition):
Dartmouth-Hitchcock revolutionizes the U.S. healthcare system
Setting a new land-speed record with Cortana Analytics Suite
Of course there are also a few funny commands in Windows 10 which you can try 🙂
Windows 10: Cool Cortana Voice Commands
So where does Cortana come from? Halo!
Halo 4: Cortana Death Scene