A professional writer “on writers, ‘digital rights management’, and the internet.”
Specifically, he cites the results of his free PDF ebook release:
The proportion of people who left a tip after downloading Trigger Happy was 1 in 1,750, or 0.057%. I am of course very grateful to each of them, though I was particularly amused by several who left $0.01, which seems a lot of clicks to expend when you could just write “Fuck you” in the comments.
That’s just sad.