I struggle with this a bit. I don't generally feel hopping-up-and-down happy when someone gets paid back in kind for their bad behaviour, but there's definitely a bit of satisfaction or even a sense of vindication. This happened when a former boss, who had been a key player in me losing a job, was indicted and convicted on business-related criminal charges. If nothing else, it helped me make sense of the misery I had experienced in my last few months at that job, and put the whole experience into the past.