This might be sort of an oddball question, but enthusiastic Google searching hasn't led me in any promising directions, whether due to lack of knowledge on my part or the fact that no one is as mean-spirited.

So, let's say I knew this ridiculously awful person, who just happened to regularly leave out semi-colons in shared PHP code, thereby breaking a website that a number of people are working on during the day. Let's say that when various entities point out the issue, this person spends at least 15 minutes trying to 'debug' the problem, despite being given the line number of the error by numerous shouting voices around the office (we just take a lot of coffee breaks now).

Say one of these frustrated workers came up with an idea one day to reprogramme this guy's keyboard so every 20th key he hit was a semi-colon, or else, to just make every key always be a semi-colon. Is there a way, either through the terminal or via a script that could be dumped somewhere, to do this?

The offender has a mac running OSX, and regularly leaves it logged in and unattended. However, he's never gone for very long, so whatever needed to be done would have to be done quickly.

Believe me, if I listed the amount of annoying things this guy did, you'd understand that he really has this coming. An entire office of PHP developers would thank you for your help, not only for the bellyache they would get laughing, but also for the distraction from the code base this would provide!