I think some of the work I am doing for CiviCRM is getting lost amongst the myriad pages in the civicrm.org's site. I'll try and define a few links here to important things I have been working on or are essential for Civi development.

http://forum.civicrm.org/index.php?topic=7239 A new way of getting and using user data
http://civicrm.org/node/503 Things I think the event system is missing
http://civicrm.org/node/511 Placeholder participant names - for PA's to use etc.
http://civicrm.org/node/524 Waiting Lists - this is making it into core.