I first looked into this sort of solution after reading an article about it what must have been 1.5 years ago. We then implemented it for Toptranslation.com (us

I first looked into this sort of solution after reading an article about it what must have been 1.5 years ago. We then implemented it for Toptranslation.com (user can create a password or just use a link to login to their dashboard). I also remember two or more stories about this scheme on HN since, which (of course) I cannot find right now :( I suppose I started noticing it more once I had actually implemented this process in a public product.