Comment by slipknotfan

> Fork Anubis. Slightly modify the hash function it computes. Deploy. Do not try to make your fork widely adopted. Do not even publish it.

A more robust solution would be to keep a few patches handy with different versions of the algorithm, and rotate which one is in use. This would keep the crawlers on their toes if they wise up to the changed algorithm. One could even imagine automatically rotating witch algorithm to use on a weekly basis.