It is looking like June is going to be quite an interesting month for participation, with a couple of projects being set up to focus on certain parts of Drupal for the month.
Last week, Advantage Labs announced Geo June, a month of focused development on the geo module. The geo module has a lot of potential to become the basis of the GeoCMS that Drupal should be (as long as the module stays generic enough), and Advantage Labs are keen to get more people interested and involved to help make that happen. During the month there are a number of physical events, but you're also encouraged to share your use cases and join in day to day with the IRC chat in #drupal-geo.
The Drupal User Experience Project also yesterday announced the launch of Microprojects to encourage user experience (UX) professionals to get involved in small bounded problems, working with a Drupal developer to implement their designs and suggestions for improvement. This seems like a great idea, not only because it's breaking down some quite large problems into bite-size manageable chunks, but also to get some outside experts - who may not have previously used Drupal - involved in the community.
If you're interested in either of these areas (or any of the other sprints which are happening), why not jump in and get involved. Having not spent much time on the Geo project yet, I'm looking to spend some time getting to know it in June and hopefully help to push it forwards, as well as starting the rewrite of the KML module to simplify it as a views display type instead of a bundle of custom code.