@18xx Other notions (mine, mostly in reaction to Bruce's):
Pays a function of the number of shares in the Bank Pool (maybe just one specific company, maybe some ability to change which company, or maybe all shares in the pool).
Pays a function of the number of companies with a stock price over $X or under $Y (possibly scaled by game phase). Get the game to race to the bottom (or a booming game economy) and it pays through the nose...
@18xx Mostly orthogonal to the who-controls-the-valuation dimension are privates that impose a clock on the game.
1871 for instance has the Union Bank which expresses a very simple concept: If the game goes slowly, the Union Bank owner wins every time (they can hold ever more shares than the paper limit). Only if the game goes (too) quickly does the Union Bank player lose. #18xx
@18xx The "problem" with the Union Bank per se is that it is a relatively uninteresting position to play.
In 1839 I am trying a partial relative: a private that pays $20 more than it did last OR (starting at $0), so the longer the game goes, the more and more and more it pays (commonly it is paying well over $100/OR by the time it closes), a similar but not as guaranteed a game-win clock, but also perhaps also a little more interesting to play. #18xx.
@18xx Privates that map to late game trains operate in a similar space. The classic example of course is the Eva from 1844 (a private that is nothing but a (non-permanent) 5-train, no revenue, nothing, just a train that you can give a company in that phase). If the game is very fast up until that phase, or that phase has a pause, then the Eva is amazing. But if the game gets there slowly...then the Eva is not so good. #18xx
Private pays/is-paid half the dividend of each share of the B&O not held by a player. If the B&O pays, they get that much money from the bank, or if it withholds, they must pay the bank the same.
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