Today I needed to create a new mailbox on Mail.ru. As always, I went to the
“Register in Mail” link
and filled in all the fields, and then came across their CAPTCHA:

2 minutes spent, did not pass. I, a graduate of the faculty of applied mathematics, did not pass the captcha. Did you succeed?
PS: read the
“code entry” rules, they are surprising in complexity. No user friendliness is needed if you are mail.ru :)