Mark Hawker has been on fire recently! His latest effort is a community-driven Health Informatics Calendar that anyone using an iCal-compatible calendar tool (Google Calendar, Apple iCal, etc.) can subscribe to. While there are other good calendars out there, most of them are company or organization focused, like the HIMSS calendar.
(Note: the calendar uses the London timezone by default, so adjust your perspective accordingly if you are based elsewhere.)
Update: Jen McCabe Gorman points out another good calendar, hosted at the Kaiser Network.
