What are some examples of computer science subfields which are in their infancy today?

Two examples I came up with were quantum computing and nanoscale computing+robotics. These are fields which (to my knowledge) are still in their infancy today but which I think will have a significant impact within the somewhat near future. It's also perhaps interesting that both of those subfields are interdisciplinary and not pure CS.

This is a train of thought along the same lines as Richard Hamming's "You and Your Research" talk (http://www.cs.virginia.edu/~robins/YouAndYourResearch.html). While I think Hamming comes across here as elitist and arrogant, he does have an interesting point: if you don't know what the important problems or areas are in your field, you can't be an effective representative.