Is it really possible to send "self destructing" emails?

This site says you can, but it seems so hard to believe.
They also say they can let you change an email you sent after the recipient has opened it.
I have no use for such things, so I’m not about to sign up, but I just wonder if the claims are possible.
http://www.pointofmail.com/learn/

I ran across one of these schemes once, and I believe the way it worked is the recipient of your email doesn’t actually get the email data, but a link to the pointofmail web site. Then when the recipient clicks on the link, the site handles the actual data transfer at that time. So you see the sender could revise or cancel the message anytime before the recipient downloaded it. If the sender cancelled it, when the recipient clicked on the link, he would merely get a message saying, “email not available”.

Any other tracking would require that the message remain on their server and all read requests by a recipient’s programs (Word, Excel, etc.) would pass back and forth from the point2mail server and the recipient.

If this were imposed on me as a recipient, I would probably tell the sender to shove off and send his stuff the standard way or I wouldn’t read it at all, but that’s just because I dislike having such controls imposed for no good reason. I can understand there might be a good reason for some security applications.

This violates just about every tenet and principle of information security, actually. Being able to alter messages without the recipent knowing is fraud - there are a variety of techniques in common use today to enforce non-repudiation such as tokens and PKI certificates that make it impossible for a person to change a sent message, even if they’re the one that sent it.

I think what Musicat said would work. Now I see what it’s for -spammers and scammers.

I’ve gotten stock tip spam before where instead of a message you got a message that was html showing a jpg on a website.
Looked like a regular html ad, but if you went back to it a few days later the site was disabled and the image would not appear any more.

Now this stuff usually ends up in the Bulk bin, but I bet half of it gets through because people like my mom never turned on her spam filter.

I can see a legitimate use. How many times have you sent something to someone and wished you could take it back before they see it? It allows an “oops” out. It doesn’t mean it was planned to mislead.

Nevertheless, I don’t like it, but that’s mostly from a recipient’s viewpoint.

My company uses something like this to send confidential information. The recipient gets an e-mail, clicks on a link, and enters a password. I have no knowledge about the rest of the claims.

All it would take would be a screen capture to save the email.