Is there a product which allows me to quickly and easily create an anonymous account on x website?

I was recently on flicker when I decided I wanted to comment on a photo. But when I went to do so I found I had to create an account. I have a burner account but it's not anon enough. So I was wondering if anyone had built some sort of extension and service which is almost like Apple's sign-in tech, but for web, and more anon than even theirs?