FileSendr Add-on complements the fileSendr application (fileSendr is another OpenNtf project). With fileSendr you upload your big attachments to the fileSendr web interface and then use it to send an email message to your recipient that contains a link to download the file.
The Add-on simplifies the process for the end users. They just mail the file in the standard way. The add-on - together with some mail rules configured on the server - moves the mail into the fileSendr application, generates the secret key and informs the recipients.
FileSendr Add-on is shipped as a Lotus Notes template (.ntf) file. The download is available here and on the website http://www.sms4domino.eu in the "Free stuff" section.
By the way.... sms4domino is a Domino based application for sending and receiving Sms messages. You are invited to have a look at the possibilities. Version 2.0 has been released on May 7, 2012. Since this version it is possible to evaluate Sms4Domino at no charge.