I have noticed multiple outgoing mail messages to an address at redut.net in my Gmail "Sent Mail" folder, all sent at around the same time. The contents are base64-encoded and upon decoding it I see my e-mail address at the end. (The rest I find unintelligible, but forgive me if I do not post it.)
I have considered the possibility that these are automatically generated when I use the "unsubscribe and report spam" feature. However, there are other messages in my "Sent Mail" folder that look more like what I would expect in that case. Those messages are sent to an address at retrevo.com, where the recipient address appears to contain encoded data, and the message contents say "This message was automatically generated by Gmail."
So, what is
redut.net, how were these messages sent to them, and what does that mean for me? Did Gmail recently change their unsubscribe feature? Is this a client-tracking mechanism? Or something more sinister?