Calling GnuPG "email encryption software" really understates its importance. It's also used in countless applications to encrypt data at rest, and GPG signatures are used to secure the distribution of software. For instance, GPG is an essential part of the package managers of Debian, Ubuntu, and RedHat. Here is a link to the donation page: https://gnupg.org/donate/index.html
Thanks for the link, just donated!
Really happy to see that this post on HN has traction, and delighted to watch the counter go up. GPG and other security projects need a way better tech PR push.