I don’t know about meeting accessibility guidelines, but I just happen to need a lightweight event calendar for a site I am doing, so in the last few days, I have been prototyping with the basic (FREE) version of Calendarix (http://www.calendarix.com). It uses php and mysql and has a great, easy-to-use admin interface. Installation is easy. You just unzip the file, create the database and modify the file cal_db.inc.php with your database name and user/password. There is also a paid version but the basic one serves my needs just fine.
It has various views you can include in your website such as a full-blown calendar where you can click on an event in the calendar to get more info on the event. There is even a mini-calendar that you can size as you want with CSS and place it in a sidebar if you want. I plan to use the mini-calendar and the view where I can get a list of events. The only problem is that the code that is generated for the list view is table-based code that isn’t formatted quite as I want it but I looked at the php code and it looks pretty simple to modify if you want to customize it and generate better looking css-based code.
Thanks for the Calendarix mention – I’m putting together a site re-work for an organization that wants an integrated events calendar and this one looks to fit the bill wonderfully. Free – or at least very inexpensive to impliment.
I’ve found it very easy to impliment so far – MySQL integration is just flat stupid easy… except for my own shortfall in not knowing enough (yet) about PHP/MySQL coding. Anyone looking to find a good calendar system needs to check it!