I recently listened to Nassim Nicholas Taleb's Antifragile: Things that Gain from Disorder (my review/reflections here). There are some game design applications, but I'm not sure I'm ready to go into detail on them.
However, I thought of something that could be interesting as a game mechanic based on the notion of antifragile things.
The basic idea is that something which is antifragile can benefit from stress and change.
This obviously has a role in games. A lot of games are basically challenge-response systems in closed loops, and each challenge offers stress. However, repetition can make it so that players no longer face a real challenge, so having something which benefits from being under stress is a good idea.
This can be represented in something like an optional time trial, but that is external to the existing gameplay loops. What I'm referring to is the notion that one should have something that functions within the core loop, like a bullet hell game that rewards players for coming just within a hair of incoming projectiles.
Risk makes games more interesting, for a start, but there is also something to be said for making changes in game states have meaningful effects.
I've got an idea which is a game in which the main resources are stress and trauma, powered by a dice pool system.
Stress adds bonus dice, which complement pools determined by defining character traits.
Character abilities can be unlocked by stress (and perhaps one can even differentiate stress), or characters can negate stress in some circumstances. This allows a meaningful choice between three paths for development: base aptitude, resilience to stress (mitigating the potential for hazard) and flourishing under stress (taking a gamble to go beyond the norm).
Stress leads into trauma, both as a consequence of poor rolls on bonus dice incurred from stress, and the fact that incoming damage is boosted by stress as well.
Characters may want stress in certain situations, since it can help them get out of trouble quicker: a bad guy might cause harm more immediately than an elevated stress level would (if you're potentially getting hit with ten dice of trauma-inducing damage, adding two more dice due to stress and getting the combat over with one less ten die roll is worth it), and specialized abilities allow characters to make decisions in line with their situation but also specialize in being in a certain place at a certain time.
My main idea for applying this is potentially in Jupiter Sovereign (I've talked about a corruption mechanic for it), but also in a sort of punk feeling or setting. Degenesis, which I'm doing some freelancing work on a supplement for, has a couple abilities that function similar to this, but it's not considered to be a core mechanic. Nonetheless, these components have been pretty well received by the community, which is a sign that they should be considered for more mainstream adoption.
I think what really makes this mechanic work is that it encourages risk. One of the things that makes a game interesting is the challenge and the uncertainty of actions, and having the need to walk along the razor's edge to really push things to the limit is a great way to keep things interesting.
And now I've got a song stuck in my head.