Hashcash, a popular comment spam protection application, has been updated to 3.0 and is currenty in Beta.
Here is the information from Elliot Back’s website:
I am pleased to announce WordPress Hashcash 3.0 Beta. In particular, it fixes several bugs from the previous release:
- Brute force guessing no longer works
- Distributed brute force guessing will not work. A machine can only make 4 guesses before it’s locked out, so to find the secret key with .01% probability you’d need 5,613 machines working on it.
- Blocking of trackbacks
Check it out at Elliot Back’s Website