What do crypto cards accelerate?

["Alexander Farber (EED)" <eedalf_(_at_)_eed_(_dot_)_ericsson_(_dot_)_se>]

Hi,

I've read http://www.openbsd.org/crypto.html#hardware
but still have these questions (since I am new to it):

  Are crypto cards only useful when using IPv6?

  Do they accelerate encrypted file systems?

  Do they accelerate mod_ssl? ssh and sshd?

  How much does the cheapest card cost?

  Is it the same "wow-effect" as buying a 3D-card? :-)

Thanks
Alex