Ask HN: Can anyone recommend a lightweight project management tool?

I'm looking for a lightweight project management tool and wondering what folks are using. I've used Trello before but would like to learn about some alternatives. Thanks in advance!

Basecamp.

Full disclosure - I work for Teamwork.com, but I use the Teamwork Projects[1] free plan for a few of my side projects and haven't found an easier alternative, you can adjust the "lightweightness" per project and just turn off stuff you don't use, then again I am more familiar with it than other tools so of course it will be more straightforward to me.

[1] https://www.teamwork.com/project-management-software

Depends what you are looking for (project management tools doesn't narrow it down much) but Trello is often seen as the competition to JIRA which seems to be used extensively in more 'old school' businesses.