You can use SecurityAssist rules as triggers. This opens up creating very complex triggers when necessary.
Must take a look - ta
RE Cron
Have a Veterinary Clinic Website
They want to send email reminders for vaccinations based on a date
I could check and run a script everytime someone logged into the admin
but that could leave gaps
Much nicer to have a script that is run, say, once a day a emails from a recordset of addresses those who are due for a reminder email?