I've seen some dark satire on HN lately. What I see here is another neat implementation of an unconstructive idea, amusing for reflecting our flaws. We really should know better than to share or encourage sharing passwords with third parties. The same goes for CC details ("enter your CC and see if it's been stolen"). The right place for a widget like this is on the signup or change password page itself.

You've put forward a little risk/reward proposition where users are unable to properly assess the risk. People love to be rated, that part's easy. You rely on them to take your word on the site's affiliation, to not understand that you can collect passwords despite saying otherwise, or vary the site's behavior mod N, or cross-match fingerprint:password with leaked/purchased/accumulated fingerprint:username data, and so on. They look at it and think, 'looks legit'. It might well be, but the proposition is unfair and its unconstructive to condition users to accept this type of trade-off.