Having played a lot of Battletech* in the day, I've done component breakouts for a few creatures - most recently a Gargantua for a one-shot in Ravinca where it was attacking the city and the  PCs had to find a way to stop it.  One of the things they found they could do is focus fire on an arm and by depleting its HP, make it lose an arm attack.  They then caused it to fall by taking out one of the legs.
* Battletech breaks a mech out into Head, Left/Right Torso, Center Torso, Left/Right Arm and Left/Right Leg, with components of outer armor and internal structure.   Once the outer armor is pierced, you have a chance to start doing critical damage to the internal structure, taking out weapons, detonating ammunition, damaging critical controls and possibly even sniping the pilot.  Once internal structure is taken out, damage transfers "inward" to the Center Torso, eventually destroying the mech entirely through attrition.
Some of this can be translated to D&D, allowing PCs to reduce attacks, negate certain abilities or hit critical weak points that feel like something more than chewing through bags of hit points.  Works for anything of about Huge size or better, especially Gargantuan+ (the old Colossal of 3E) from being just a slugfest vs. hit points.  Somewhat reminiscent of the old "Shadow of the Colossus" video game.