Tired of sending plain text email messages from your website? Now
you don't have to... this sample will show you how to send email
messages that can be as lively as a web page from ASP.NET.
Aside from formatting the body of your message as HTML, the key to getting HTML-formatted
email working is setting the BodyFormat attribute of the MailMessage object to MailFormat.Html.
Until you do that, most mail clients won't render the HTML. The message will just appear
as plain HTML and will look as if the user did a "View Source" on a web page.