The All-in-one Event Calendar  is a very robust and versatile plugin for WordPress.

This free plugin, made by The Seed Network, a group of Canadian developers,  combines a clean visual design with a powerful set of features that have been designed with business, organizations and communities in mind.

All In One allows you to create one event and have it displayed on a few or a few thousand calendars with no extra work. This calendar is a powerful service for websites and bloggers that will make it easier for you to publicize events, courses and offerings with your colleagues, clients, and community.

Monthly calendar or agenda style views of the calendar are available and events can be filtered through customized categories and tags.

Other top features include: recurring events, easy sharing with Google Calendar, Apple iCal, MS Outlook and any other system that accepts iCalendar (.ics) feeds and embedded Google Maps.

We recently set it up for one of our clients, Next Generation Trust Services, and we were surprised at how easy it was to set up and configure.

ONE SMALL PROBLEM

The only issue we had is that the first expanded box is a fixed height so if your text goes over a certain character count (not sure what that number is) it gets cut off.  The only way we found around that was to modify the plugin code ourselves to add a scroll bar.

But other than that little issue, we found the All-in-one Calendar to be a perfect event planning plugin.  You can download it free through the regular plugin search function in your WordPress dashboard, or grab directly it at The Seed Network website.