From my other website, though I would share here too.
A Steve Special this one. Tiger came with sha* digests binaries, but not Leopard. So here is how you can get them back. Insert into your .bashrc:
alias 'sha'='openssl dgst -sha'
alias 'sha1'='openssl dgst -sha1'
# the following lines only applies if you have openssl installed via darwin ports
alias 'sha2'='openssl dgst -sha256'
alias 'sha5'='openssl dgst -sha512'
Usage is simple, for example: