Do you regularly send out mass emails? Mail Man is designed just for that purpose.
Of course, you can send mass email with any email client, but Mail Man allows you to import email lists and group them any way you want so you can easily select a targeted group to email.
Mail man features an email editor, which allows you to create emails, and an HTML editor so you can create attractive newsletter style mails too. For the HTML uninitiated, there are various templates included which you can edit yourself. However, there is no wizard/tutorial to take you through creating your own HTML-rich message.
To send email you have to associate your email account with Mail Man. This means having to find your SMPT server, username and password. This isn't too technical, but a more automated system would be more user friendly.
Importing contacts is pretty simple, although drag and drop functionality would be a great improvement too. Once contacts are imported, moving them is difficult - again, dragging and dropping is intuitive, but you can't do it. To move a contact you have to copy it, then delete the original!
It's not perfect, but Mail Man is a pretty useful tool for mass emailing once it has been set up.