Ask HN: What side projects are you working on?

It's the weekend - let's give everyone's side-projects a boost.

In particular, I'd love to hear about anything that could use input from other HN readers, but perhaps isn't ready for the Show HN firehose.

Inspired by https://news.ycombinator.com/item?id=14718089 - lots of awesome projects in there fizzled out from lack of beta users / marketing.