With the changes in technology, we have to always keep learning new things. It is very well expected to answer this question during an interview. The trick with this question is that we have to tell the technologies that are relevant to the business of the organization we are interviewing with.
Another solution for this is to learn a generic new technology and use that in our answer.
But whatever topic you mention, be prepared to answer follow up questions on that.
Sample answer is:
I have recently learnt Amazon Web Services. Though my current company does not use it, but out of my interest I have attended an online course on Amazon Web Services. Now I can deploy an application in AWS cloud. I have done a proof of concept application to deploy my application in AWS. It works well and gave me good insights into the cloud-computing domain.Read the full book at www.amazon.com