(Today my graduate research class begins; here is advice for new researchers.)

"Son, don’t marry for money; hang around rich girls and marry for love." A joke I heard years ago from Chip Morningstar. 

Research topics work similarly.  Don’t research a topic because it is popular; expose yourself to many popular topics and you will fall in love with a few.  Fall in love with a dozen topics; too few and you’ll linger too long after they fail. 

Really gushing on Hanson today. My apologies, but I think we're all better for it.