'Alert me' button not available in SharePoint 2010 lists

A couple of days ago I was playing around in SharePoint 2010. I wanted to place an alert on a document library but noticed the "Alert me" button just wasn't there. It was available though in the ribbon when watching a page. The reason for this is that you probably don't have an outgoing SMTP server configured in the central administration. Just configure it there and you will see the button!