A few of us started to quiz ourselves amongst our friends, partially influenced by pub quizzes I've attended/conducted, and Kumar Varun's Kvizzing.
Our motive wasn't to compete but rather to learn. We craft questions on anything we're curious about, and offer takeaway bits of knowledge, irrespective of whether we knew the answers.
Hence, we extended it to https://quiz.rack51.com/. There are no scores or ratings; it's simple, have fun and learn one fact a day.