...there's Jira. Yes, I know that Jira is absolutely not written for GTD. It's "aware" of Scrum and of Kanban, and other things, but as far as I can tell, not GTD. The main reason I'm looking at Jira is for work--for a Kanban-style workflow in Jira Software for a very small but growing team that has to support a number of projects. But as I play with it, I find myself thinking of what I could do with it to support a sort of Personal GTDBan or Personal KanGTD or whatever you'd call it--a GTD implementation that ties firmly to a Kanban-style workflow and WIP limits. Poking around, it appears that - Jira issue types could be used for contexts. - Jira stories could be used for projects. - Jira projects could be used for areas of focus, or for "folders" in OmniFocus, or any other above-project organization that's wanted. - Backlog, and the way that backlog can be pulled off the Kanban board to get out it of your face, could be Someday/Maybe. I think that I could add another status, and have both Someday/Maybe and Backlog. Or I could have a Jira "project" just for Someday/Maybe. - The ability to make custom boards would support a lot of different cuts on the data. - The ability to link to Confluence could be used for project support material. - The Kanban board could be used for, well, kanban. - The Epics and Versions capabilities are very interesting. Probably no real GTD-like purpose, but, interesting. One possible down side is that Jira is obviously intended for programmers. I've discussed the research that says that programmers have one way of making mental models and the rest of the world has another, and this is very obviously intended for the programmer view. One up side is that you can use a demo of Jira Cloud for a month for free. One down side is that after that, it's ten dollars a month--a lot more than you'll spend on OmniFocus. I may decide that it's worth it anyway. Another up side is that Jira Cloud does appear to support local backups, so if you decide to flee, I think you can get your data out.