If I could have back the time I've spent resending emails when I forgot to
actually attach email attachments, I could spend less time sleeping and eating
and more time doing necessary stuff (thanks TanookiTravis). I need my email
client to ask me something like this: "You're trying to send an email in which
you say 'I've attached the report', but there is nothing attached to the email.
Are you sure you want to continue sending?"