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Heartbreak. We all experience it as sports fans, and sometimes it resonates more and lingers longer than victory.

How to quantify heartbreak? That was the question I had to ask after we came up with the idea of looking at the most heartbreaking outcomes in playoff history. The metric I settled on was championship probability, as in which teams had the best chance of winning the title at any given moment of the playoffs but ended up falling short.

As you might imagine, this is particularly relevant as the San Antonio Spurs prepare for a rematch with the Miami Heat 12 months after coming within a defensive rebound of beating the Heat for the NBA championship. The Spurs had the Larry O'Brien Trophy in their hands until Ray Allen snatched it away with his tying 3-pointer. That's heartbreak.

Not every title that slipped away has done so in as dramatic a fashion, and not every heartbreaking moment necessarily involved a likely championship -- you won't find my most heartbreaking moment as a fan -- the 1994 Seattle SuperSonics losing to the No. 8 seed Denver Nuggets -- on this list because it happened too early in the playoffs. But you will find as many different ways to lose a championship as there are teams on the list (30 in all, dating all the way back to the start of the NBA).

Enjoy, if the memories aren't too painful.