Sunbird

I like open source and I think this works very well with the provider application, has a nice UI - only its slow. Like hell.

poor UI. And very careless web sync. It make impression, that developer made this utility on pain of the death penalty.

But it works.
PS. On mozzila.com there is no record of sunbird. Last version was more than year released. Looks like somebody killed developers...

poor UI, and performance, I should say..

Good because I can have it sync it with google cal. and then have my iPod touch sync with google cal so its good for a 3 place sync (local, web, iPod).

I like to use this separate from Thunderbird because I think it loads faster since it is smaller than Thunderbird+ lightning.

was into it before, now I just use the lightning extension for thunderbird instead. I think they're the best free calendar apps I've seen for WINDOWS

Good calendar if you are looking at one that is cross platform - works very well on both windows and OS X.

One of the best extensions is "Provider for Google Calendar" - available at https://addons.mozilla.org/en-US/sunbird/addon/4631 . This extension allows syncing the calendars with Google Calendar and hence if you are using multiple computers, all the calendars have all your events. Truly useful!

Good start for a stand-alone calendar application. (version 0.8)

awesome awesome program!!

its not that widly known so there arn't that many add-ons for it but other than that the program is wonderful

Bwa, I don't find it that great actually. There's a lot of room for improvement. But the program isn't that old either. So I hope improvements are coming up. Let's hope it becomes as good as firefox...

I love it, another great product by Mozilla.