This is a real life problem that many face. You have a calendar in your cell phone for immediate appointments, you use google calendar extensively, for the sms reminder and public event sharing. You also have Sunbird/Thunderbid to manage your local schedules.
Wouldn't it be great if you can synchronize them all at once. Let me show you how easy it is
Step1: Sync Sunbird/Thunderbird with GCalendar
Thunderbird has a nice addon called Lightening, which adds calendar support to Thunderbird. It makes for a killer Sunbird/KDE PIM replacement.
Once you are done installing it,
install the Google Calendar Provider addon.
This gives you bidirectional ability to read and write google calendars
Setting up your remote google calendar on thunderbird/sunbird is very easy. Just go to File > New > Calendar > Network Calendar > Google Calendar
and paste the private html url of your google calendar
Read this graphical tutorial, if you don't know where to find it.
Congrats!. That's it. Once everything is setup, you can read/write your google calendar directly from Thunderbird.
Step2: Sync your phone with GCalendar
There are lots of tools available that help you do this. My personal favorite is GooSync. This allows you to directly sync with your google calendar over the air via internet. Register for a free account and try it. The steps are pretty explanatory.
All you need to do is :
a) select your phone model,
b)give your phone no. so that it can send you the sync settings
c) Select your google id by authorising it to access your calendar
d) Select the calendar (free version allows you to sync only 1 calendar)
e) Wait for the settings sms.
f) Save the settings in your phone and sync.
(note you need an access to the internet on your phone)
viola! Your phone is now in sync with your thunderbird and google Calendar.
No more missed appointments, hassles of unsynchronized calendars and using complex tools (specially in linux) to sync your mobile and your desktop calendar