Drove home quite aggressively the other day, and when i got home i smelled some kind of burning.
I smelled under the hood, nothing there.
I smelled my tyres and brakes, not there.
Took a look under the car and saw smoke, or steam of some sort.

It was all coming from one end of of cat.
There was a palm sized area of jet black on the end of the car, and stinky smoke was coming off the surface.

Have i mushed something?
Do i need new cats? (if so how much and can you go cheap aftermarket?)
Is this not the cats fault and something else is going off?