I just stumbled upon http://whatcanidoformozilla.org/. You basically click buttons until the web site suggests a project that overlaps with your expertise. The [code is free](https://github.com/jdm/asknot) and we could easily use it for our projects. It would be great to have something similar, perhaps under https://www.torproject.org/whatcanidofortor/. A technical downside: it requires JavaScript.