I fried the battery charging chip for my HTC dream when I rooted and used it as a router for the family in holiday. I felt it was hot to the touch but I thought "it's gonna be ok, surely it has temperature sensors and it will throttle". High draw for a long time when charging = the chip exploded and it wouldn't charge anymore. Luckily the battery was removable and I already got an external charger for it from dealextreme. But HTC still repaired it for free under warranty even if it was my fault and I gave to them back rooted.

Same for LG when my rooted Nexus 5X boot looped, although that was an endemic problem caused by LG shitty manufacturing (they changed the stance a few months after that, never bought LG anymore)

Samsung should repair it, I thought they were the only ones root friendly left on the market...