Most OSR rules hackers are probably familiar with "Let the Shield be Broken". It has appeared in a number of OSR games like Delve 2e and ICRPG. Here is a quick summary, if you are not.
Let the Shield be BrokenIn combat, if you are using a larger shield (i.e. not a buckler) and take damage, you may instead choose to let your shield be destroyed and take no damage.
It is an exciting, cinematic rule that doesn't slow down combat very much, and makes shields way cooler.
Delve 2e, has a detailed system for defending yourself with your armour, and has rules for gear degradation as a cost for doing so, It serves a similar function to Let the Shield be Broken; you trust to your mail, letting it be battered, dented, and torn so that you can focus on the offensive.
The idea of a warrior charging forward, heedless to his armour being reduced to scrsp seems equally cinematic and exciting.
I decided to hack the rule into my current DCC RPG campaign. Here is the result:
Let the Mail be RentIn combat, if you are wearing armour and take damage, you may choose to take half damage, and reduce the AC value of your armour by 1d4. If it reaches 0, the armour is destroyed, but you still suffer armour check penalty and reduced movement until you take 1d4 rounds to temove the ruined gear.
Damaged armour takes time, attention, and resources from a blacksmith equal to 10% of the armour's cost per point of AC.
This rule is not quite like the armour rule in Delve 2e., in fact, it is barely recognizable from the source material. I simplified it by removing armour hit points, and instead let the AC bonus the armour provides serve as its sole resource to be sacrificed. If you let the armour suffer the damage for you, it protects less - possibly a lot less.
What it does do is essentially the dame: make armour more useful, while offering the PC a Devil's bargain: "You can avoid getting hurt now, but if you do, it will be easier to hurt you more later."