Damus
nostrich profile picture
nostrich
The proof of work contact form on my web site has a difficulty adjustment. I can it the annoyance adjustment. Any time I start getting annoyed by the volume of messages I receive, I bump up the difficulty.

I started off 5 years ago at about 30 seconds worth of hashes on a desktop CPU and now am up to 10 minutes.
2
douglaz · 24w
Proof of Work? Such stone age technology. Have you tried fixing the filters? /s
Han Sanders · 24w
It probably adjusts only one way, as getting little messages is less of a nuisance than the nuisance of adjusting the difficulty? In general, people are better at taking note that they're annoyed than at realising that they aren't annoyed.