We just recently launched an addin for Microsoft Outlook® desktop that has two main features right now.
The first one warns you and can stop sending e-mails where you have accidentally put your mailing list in the To or Cc field instead of the Bcc field.
When you have more than a certain number of recipients (user definable) in the To and Cc fields you get a pop up asking you if you are sure to send it after you press the send button.
This way you can catch it when you pasted the list in the Cc instead of the Bcc field.
The second one allows you attach files to received e-mails just like you do on sent e-mails.
This is great if you want to attach PDF invoices you downloaded through a link in the e-mail, PDFs of payment receipts or contracts or just a document with notes you made for yourself (for example on a follow up phone call) that you want to keep with the e-mail.
So go to http://makbiz.link/MAK_Outlook_Tools and check it out. It may be useful and help you avoid embarrassment or even legal issues.