I found this the other day :
DotNetOpenMail allows you to send email from applications which use Microsoft's .Net development framework, including asp.net, C# and WinForms.
It is a freely available open-source component written in C# that makes it easy to create HTML and plain text email with file attachments without needing the System.Web.Mail library. A programmer can use it to create multipart/alternative, multipart/related and multipart/mixed MIME messages in various character sets and various mime encodings such as quoted-printable, 7bit, 8bit and base64 without needing to know too much about the details."
It is in beta stage(when this is posted)
Þorgeir [ rusl ( at ) hot dot is ],