Crypto-dongle protocols?

[fnerd@smds.com (FutureNerd Steve Witham)]

I know there was talk of making little crypto
boxes that attach to the back of bigger computers.
"Crypto-dongles," they were called.  Did anyone go and
build one?  Did anyone think up a protocol for talking
to one?

It occurs to me that pocket computers like the Psion
might make nice crypto-dongles, especially for people
who use Unix for mail.  The little computer could show
you the text you were signing or that it had decrypted.
All safe from Unix hacks--but is there a good protocol?

Integration with PGP functions would be nice and might
even ease the implementation.  So, once again,

Has anyone got a crypto-dongle protocol?

-fnerd@smds.com
quote me

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