One of my favourite games among those with a minimal set of rules is 'No Thanks!'. When it is your turn you have only two options: pay one coin to reject a card or take the card and all the coins that have been paid until then. At the end of the game, in which one tries to score as few points as possible, each player sums up the value on the cards that she has collected with a twist: a sequence of consecutive cards is only worth as many points as the card of lowest value in the sequence. This simple idea is enough to break simmetry among players and make the game interesting.
I think it would be cool to list as many scoring systems as we can, where cards/tiles collected over the game are scored at its end. A good format could be:
Game. Scoring system. Highlight of how it impacts the game.
Looking forward to reading about spicy scoring systems.