Great find!
404 pages and unsubscribe links are an awesome place to opt people into your service, whether it's to sign people up like in your example or Groupon's email opt out page which is a great way to opt people back into your newsletter.
http://www.youtube.com/watch?v=nAve7L7An4Y
We've ran several test that show a high increase in signups via 404 pages.
Depesh Mandalia
Reminds me of this - http://explicitly.me/robots.txt
I'd put it down to clever marketing tactics
Talia Wolf
Great find!
404 pages and unsubscribe links are an awesome place to opt people into your service, whether it's to sign people up like in your example or Groupon's email opt out page which is a great way to opt people back into your newsletter.
http://www.youtube.com/watch?v=nAve7L7An4Y
We've ran several test that show a high increase in signups via 404 pages.