[withinboredom]

My blog does a proof-of-work before submission (withinboredom.info) in your browser. It'll use a fair bit of cpu power, but should only take a few seconds to complete. For an attacker... that's quite slow and self-limiting.

[eduction]

I did Ctrl-F on "proof-of-work" in this thread to see if anyone had tried this, you seem to be the only one. Seems like a good precaution before sending even a verification email.

Did you have to roll your own or was there some proof of work library you were able to use?

Update: Ah, found the code - https://withinboredom.info/posts/how-this-blog-actually-work...