One of my consulting clients sent me a frantic email today, reporting that a PHP script that I had written for them had stopped working. I tested and verified the problem, analyzed the debugging information provided by the script, diagnosed that it was caused by a bug in a third-party API, modified my code to compensate for the change, and published the fix to the client's webserver, all in under ten minutes!

It always feels good when I can quickly provide an effective solution.