Per HAncock4:
Danis' does not seem to fully address the problem. The user's phone
still rings and the user still has to divert their attention away from
the task at hand.
Nomordobo seems the most promising - but it's probably going to involve
a monthly fee - and I don't see the diff between it's audio CAPTCHA and
a user-controlled challenge/response (something like "Press 1 for Sue,
press 2 for Dave, press 9 to connect" Where the "real" digit is buried
at the end of the prompt.... and there's a user-maintained white list so
frequent callers just ring through with no challenge.
Realistically, I'd expect us to be using whatever Google comes up
with...
--
Pete Cresswell