Was just about to link this! My favorite excerpt:

“Would anyone actually go to the trouble of disassembling and studying 100K or so of incredibly tight and bizarrely threaded 6502 machine code just to tinker? As it turns out, the answer is yes. People did. We were not 100% rigorous in following our own rule. It turned out that there were a few features whose implementation was greatly eased by breaking the rule in situations where, in our judgment, the consequences would not be material if some people "cheated" by hacking their own systems. Darned if some people didn't hack their systems to cheat in exactly these ways.”

> Yet another spent over $1000 in one month in Habitat. At around $300 and $600 dollars, he was mailed a message suggesting he "check out his usage in the billing section". If we could get 20 more of this type of "rich" user, we would be profitable!

Already landing on the "whale" method so familiar in games today. Sadly Habitat didn't have the benefit of microtransactions to break through the pesky limit of minutes in a day to really take advantage of this phenomenon.

One of the best reads is "Lessons from Habitat" [1]. While things have changed in the 30 years, one of the conclusions is still valid nowadays: the implementation is relatively unimportant.

The entire paper is a gem; worth checking it out. It has aged wonderfully well, and I never get tired of re-reading it over the years.

[1] http://www.fudco.com/chip/lessons.html