[boredzo]

If we tried to pour the collective total of human stupidity (artificial or otherwise) into a single program, it would exceed the capacities of all the storage devices ever made, past, present, and future. :-)

Honestly, if I were writing this today, I'd make the “worst” example less bad. What you see here is way too fantastic. 2011 Me would make it realistically bad—the sort of thing a new or just plain apathetic programmer might write. I wonder, though, how much it would differ from the canonical one-liner.

[singular]

I think the best kind of example would be one where the problems weren't at all obvious, yet were rather fatal.

[boredzo]

Maybe so. Perhaps one example fault would be testing the result of fputs against 0 rather than EOF…