something from nothing... (Score 1)

Most games I know of that avoid the zero-sum paradigm are driven by improvisation or recall. Theatre games like "Freeze Tag" or "Yes, and..." fall into the first category, while trivia games fall into the latter. Some versions of these games have points or serial player elimination added to provide an arbitrary end point, but these aspects are often arguably extraneous. There have also been a couple card games released recently, most notably "Flux", where although there are zero-sum aspects, the rules are changed dynamically during play -- forcing more dynamic kinds of strategic thought.