Here is a cheeky shortcut to quickly add new events to your Google Calendar!
http://www.google.com/calendar/event?ctext=%s&action=TEMPLATE (right click and add it as a bookmark!)
By assigning this a keyword, such as cal, you can quickly add events by typing cal followed by your event details, in human language, into the Firefox address bar!
This will take you to the event add page, where you can change any details and submit it to your calendar!
Update This did have an image, but it has disappeared!