My most humbling experience was finding the source code online to the original Pokemon games. It was right after I had finished my first text based Linux console game and I was looking up other programs source codes just for shits and giggles. Most of them were simple and I learned a few simple tricks but the red and blue Pokemon were the first codes I saw that fascinated me. The addressing, the memory allocation, even the simple audio processing was simply genius. So many unique innovations and techniques. If I achieve 1/5th of the skill I found in those files, I can die a happy programmer!