Endings you have to know

There are all endings we "have to know" ie ones guaranteed to bring home the point (or save the half point). The Lucena Position and the Philidor Position are 2 such examples, and of course there are many more. However I suspect the list of endings I "have to know" might not be as extensive as the endings a 2400 rated player has to know. And once you get into the 2700+ range the list might be both long and increasingly obscure.
Of course one of the reasons why club players don't collect as many positions as stronger players is that we aren't forced into as many endings, either due to our games being decided by "the last blunder" or that out opponents play inferior moves in these endings, making our task easier.
Such knowledge, and its application, was quite apparent in the round 6 game from the Tal Memorial between Kramnik and Ponomariov. In a R+P v B+P ending, Ponomariov's bishop was defending his pawn and White had to force a zugzwang position to win the pawn. According to the Chessvibes site this was a similar ending to the 1979 Timman v Velimirovic ending from the 1979 zonal, and while I have no reason to dispute the additional claim that every Dutch chessplayer now knows how to play this ending, I wonder how many other chess players (apart from Kramnik) are familiar with it as well.
The diagram position is not from this game but from a much older game between Euwe and Hromadka. A similar kind of ending (although White does not have a pawn), there is a right way and a wrong way to play it. In "Training for the Tournament Player" Dvoretsky says "you either know it or you don't"