A couple of sneaky tricks

[Gregstrom]

There was a report in the Hall of D'oh! thread of a Cyclops picking up an Eye. That behaviour could have been patched out since then, of course.

Armour of Twisting Thorns is another interesting possibility for cursed item planting, by the way. +1B/N isn't a big issue if your enemy doesn't have those paths, and the 5 enc is a pretty big penalty for just about anyone who ends up with it.