The 2015 Nobel prize in physics went to Art McDonald and Takaaki Kajita for the discovery of neutrino oscillation at SNO and SuperKamiokande, respectively.
Now, for those readers who are not familiar with all this, do not get the impression that these two were working all by themselves and then discover these. They did not. There were huge number of people who were working on these projects, and the papers they produced listed a large number of authors. However, these two were either the leading scientist or the most prominent/significant figure representing each group. This is not unusual for an experimental discovery, especially in elementary particle physics, where the most prominent figure is singled out for the award.
When I read this, I must admit that I was a bit surprised. Not surprised that they are awarding it for the discovery of neutrino oscillation - it IS a major discovery. I was surprised because I somehow thought that this discovery had already been awarded the Nobel prize already! I mean, it was such a significant moment, and it is now already accepted that neutrino oscillation is a fact, that I somehow assumed the Nobel prize had already been awarded for this discovery years ago. Obviously, I hallucinated that one.
Maybe the Nobel committee were debating all this time on who should deserve to receive the prize, considering the huge number of people involved, with several prominent physicists deserving it on each group.
In any case, the prize for this discovery was long overdue.