It is now possible to send out email reminders for events via brim. (This currently only works for non-recurring events)
There are a few things to consider:
How to enable reminders for calendar events sent out per email?
You need to add a line to a crontab (or anything similar), that periodically executes and fetches a predefined page in Brim.
For unix, the following line executes the reminder mechanism each 5 minutes:
*/5 * * * * /usr/bin/lynx --source http://_YOUR_SERVER_HERE_/brim/brim.php?plugin=calendar\&username=calendar\&action=sendReminders
(Important to add the backslashes just before the ampersand!)
Furthermore, you need to enable this feature as admin user. Go to the configuration section and turn this option on, it will be disabled by default.