Fucking Tripcode Explorer, how does it work?

How the fuck does tripcode explorer generate a random string then unix crypt it at over 1M per second?

I'm trying to do something similar but with (salted) md5 hashes, and it can only get to 18-20K per second.
I'm using a ~700ish MHz PPC processor with limited resources, by the way.

For the record, the fastest crypt implementation available in the wild is still John the Ripper's, though it's a bitch to integrate that into your own code. Most people (including Xarn) just use OpenSSL's DES_crypt, which is probably the fastest non-bitslicing implementation.