SMTPMail

From Randem Systems:

When you need to send out email announcements to your clients and your ISP will only let you send 10-20 at a time, this program will ignore those limits. Use replacable information and hyperlinks in your emails. Prepare a RTF file with your message and just import it into SMTPMail and let it do the rest. Create multiple templates for different situations and products. Work with SMTP Authentication.

View trasmissions logs to determine why emails failed and how many were sent successfully. There is even a test mode so that each email send will come back to you for testing purposes.