yeah, it's called mcvert and it's available from the various archives that 
support a/ux. (wuarchive?) I've compiled it real nice on a sun4, and i'd expect
that it's device-independent enough to do it for mac68k. It does a couple of
things, including binhex, unsit and unpit i think.

(I have no real use for it anymore, because it's easier to send asciis through
cheesy unix things)

-John