While I haven't had ANYTHING Cryo-treated myself, I have noticed an alarmingly significant increase in the number of "cryo-treated" used cables for sale on Audiogon - but were not advertised as such.
While there are many folks who suggest that cryo treating cables is the best thing since sliced bread, I would presume that most of us who buy used cables often, would like to know the truth behind the history of the cables.
From what I have read, CT works well on some items - but can destroy others.
For those who read this - please remember to ask the seller before buying used cables (and other components) whether or not the item for sale has been treated. I'm sure you do not want be the sucker who spends hard earned cash for someone else's scientific experiment. As far as I am concerned, if a used cable has been cryo-treated, it is worthless on the regular used market.
For those of you who brave enough to have cryo treatments done, here is the name and number of a source.
CyroPro (888)300-2356 talk to Dave - I believe they charge 10 bucks a pound for the service.