Since it's Saturday and much of my readership will be indoors watching the aftereffects of assorted storms/hurricanes, here's a claim someone might want to track down (I did ask on the Classics list ... didn't get far) ... in any event, the Register has an item on tickling which makes the claim, inter alia:

Tickling was used as a torture by the ancient Romans.


... this comes up semi-regularly. Has anyone ever seen (outside of Asterix) that the Romans did use tickling as a method of torture?