How to send an email on event (with event details) in Windows 7

How do I send an email with event details when some event occurs in Windows 7, for example when any user logs on?

I've tried to use Event Viewer, but I haven't found out how to attach event details to the email's body.

Answer

Use the task scheduler from the (Control Panel -> Administrator's Tools). It has the option to run a script, program or action, depending on some trigger (like someone logging on, running a program etc) Here's an example setup dialog (you are interested in the event "at log on") :