I'm the creator (often with others) and maintainer of some very popular Perl distributions that are used either by many other libraries, many applications, or b

I'm the creator (often with others) and maintainer of some very popular Perl distributions that are used either by many other libraries, many applications, or both. The most notable are probably DateTime (https://metacpan.org/dist/DateTime https://metacpan.org/dist/DateTime), Log-Dispatch (https://metacpan.org/dist/Log-Dispatch https://metacpan.org/dist/Log-Dispatch), and Exception-Class (https://metacpan.org/dist/Exception-Class https://metacpan.org/dist/Exception-Class), among many others. The first release of DateTime was in 2003. In 2008, I added a "DONATIONS" section to the docs, and around that time I started adding it to everything I released. It was basically just a link to web page with a PayPal button it, so not very professional. Over the years since I started doing this, I'd estimate I've gotten somewhere between $1,000 and $5,000 (PayPal doesn't offer historical data far enough back to know for sure). On the one hand, that's a lot of "free" money. OTOH, this is software that has been used by absolutely massive companies, including Amazon (which I know for a fact used a lot of Perl in the early days, including things I worked on). So even $5,000 is an incredibly small fraction of the value this software generated. Almost all of these donations were $100 or less and seemed to come from individuals. I can only recall one instance where someone asked for an invoice first, after which their company donated $500 (or maybe 500 euros), which was nice. So this is just another data point. And then I realized that this link has been broken since some time in 2018. Doh! I'm fixing it and adding a "email me for an invoice" bit as well. It can't hurt.