Calendar:Lightning - wiki.mozilla.org

If the folks working on Thunderbird can implement a simple calendaring and task mgmt system with hooks into Exchange, I just might be able to ditch Outlook altogether. I gotta check this out, as I recently switched back to Outlook after using Thunderbird as my mail client at work for the past month. The only thing I wasn't able to do (which really blows) is accept/reject meeting invites. My workaround of syncing with My Yahoo! Calendar works, but is a less than desirable solution. The cool thing with using My Yahoo is setting up SMS reminders for meetings that are delivered to my razr. very helpful...

Calendar:Lightning - wiki.mozilla.org