Nowadays. Nyssa has become much more. Nyssa is now used to describe (often in all capitals "NYSSA") any sort of person that you feel needs to be knocked down a rung or two, jokingly or not.
Most commonly used jokingly between friends, such as "YOU'RE SUCH A NYSSA, LOL" on chat sites. It has become a recent small internet "meme" and even has its own facebook group.