Tracks is a web-based application to help you implement David Allens Getting Things Done methodology. It was built using Ruby on Rails, and comes with a built-in webserver (WEBrick), so that you can run it on your own computer if you like.
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I have been using tracks for some time now, as it was the best choice I could find for a ToDo software that was simple but also good looking, like some of the commercial applications that are out there. Since recently I had to move my installation to another server, I thought to document it and hopefully this might be useful for other peoples also.