PyCon is a Python conference organized by its attendees to keep the costs down. There's usually a keynote address by GuidoVanRossum, other keynote talks, dozens of refereed paper talks, Lightning Talks (10 minutes max), Open Space (quasi-impromptu discussions), BOFs (Birds of a Feather, quasi-impromptu discussions), sprints (a few days before or after the conference to hack with others on Python projects), and time to meet other Pythoneers individually. The first two conferences were held March 2004 and 2003 at George Washington University in Washington, DC. This wiki's MainPage has links to articles about the previous conferences.
More information is at http://pycon.org/
Thanks to Ted Leung for his notes. It sounded like a lot of fun. -- JeffSandys