You know the old joke about the prison where all the prisoners all knew the same jokes, so instead of bothering to tell them at dinnertime, they would just call

You know the old joke about the prison where all the prisoners all knew the same jokes, so instead of bothering to tell them at dinnertime, they would just call out a number? Seems like the interweb is like that, except it's XKCD comics instead of joke numbers. There is one for every occasion. With that in mind: 624.