I'm going to go technology on this one: The Wearable Holodeck.
We're just talking about Augmented Reality + Wearable Haptics. No new technologies or 'sci-fi' inventions, just refinements of what we already have.
I think that we'll see the Wearable Holodeck really come into its own when it comes to economic decision making. It would mark a dramatic shift away from low-quality disposable goods and towards ones that either enhance the existing experience (more cameras, CPU power, etc.) or that provide things that it cannot (comfort, food, etc.)