iCal

Compact Header – Stylish script that gives you more space by removing the header of Google Calendar.
Extra Tabs – User script that changes the custom date range tab to multiple tabs of your choice.
Full Cal – Add-on gives you a larger view activated by a customizable hotkey.
Google Air Skin Greasemonkey hack to give Google Calendar, Gmail (), Google.com, and Google Reader () a nice skin.
Google Calendar Optimized – User style that compacts the paddings and margins and lowers the font size.
Header and Navigation Switcher – Hide the navigation and header bars with this user script.
Show Week – Greasemonkey addon that adds week numbers.
Slate Series – Grey user style skin, ideal for those depressive autumn days.
Textwrap Events – Wrap long event names so they’re actually readable.
Wheel View – Script to let you move the calendar with your mousewheel.
Add Your Agenda To Gmail – Tutorial on adding your Google Calendar agenda as a Gmail sidebar.
Facebook to Google Calendar – Greasemonkey script to send Facebook () events to Google Calendar.
Google Calendar Forecast – Adds your agenda to every webpage you visit.
Google Calendar Widget For TypePad – Put your calendar in a sidebar for your TypePad () blog.
Howto integrate Google Calendar in you website using AJAX – Short tutorial that shows you how to put your agenda into your website.
iGoogle Calendar Gadget – A simple Google Calendar gadget for your iGoogle homepage.
Remember the Milk For Google Calendar – Add your RTM to-do list to Google Calendar.
WoogleCal – Adds Google Calendar to your WordPress () blog.
Add Your Agenda To Gmail – Tutorial on adding your Google Calendar agenda as a Gmail sidebar.
Facebook to Google Calendar – Greasemonkey script to send Facebook () events to Google Calendar.
Google Calendar Forecast – Adds your agenda to every webpage you visit.
Google Calendar Widget For TypePad – Put your calendar in a sidebar for your TypePad () blog.
Howto integrate Google Calendar in you website using AJAX – Short tutorial that shows you how to put your agenda into your website.
iGoogle Calendar Gadget – A simple Google Calendar gadget for your iGoogle homepage.
Remember the Milk For Google Calendar – Add your RTM to-do list to Google Calendar.
WoogleCal – Adds Google Calendar to your WordPress () blog.
Google Calendar Notifier – Firefox add-on with easy notification for today (and tomorrow)’s agenda.
Google Notifier for Mac – Get Gmail and Google Calendar notifications with this handy app.
IMified – Add events and view upcoming tasks through AIM, Yahoo! Messenger, MSN, Jabber, or Google Talk.