It seems that using cellular automata for hash functions is a viable option according to that paper: http://download.springer.com/static/pdf/386/chp%253A10.1007%252F3-540-46416-6_17.pdf?auth66=1405789057_31fc1522b59f8110ad57d060b99b9ccc&ext=.pdf I wonder how well my Rule 30 hash function performs. I have no clue how to test it. It would be good to have a general test that can be fed a bulk of sample hashes. I found this: http://hashtest.sourceforge.net but I can't determine whether the test is useful or not. I guess I need to learn more about cryptography.