We took Duncan to see the Lego Movie recently, and I have to say... I thought, when seeing the previews for it prior to seeing Frozen, that it'd be one of those movies where the previews show all the good parts and the rest of the movie is just filler. I was actually pleasantly surprised.
But hearing the little boy say afterwards "I want to be a master builder" made me think about the bucket of Lego that's sitting up the storage shed, and I decided to go fetch it for him. It worked out to be a pretty good carrot to get him to eat his dinner well, and we dumped the bucket out so he could play while I sorted out the pieces that didn't fit (because they'll only serve to frustrate him).
He's also been amazingly good at putting them up when it's time for bed. We'll see how well that continues.