Now, we can use .NET Framework 2.0 and 3.0
$mailer = new-object System.Net.Mail.SmtpClient("smtp.xxx.xx.xx")
$mailer.Send("from@xxx.xx.xx","to@xxx.xx.xx","Subject","Body")
http://msdn2.microsoft.com/en-us/library/system.net.mail.smtpclient.aspx
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