  Recently introduced toy surface plasmon "black holes" and "wormholes" (New
Journal of Physics 5, 147.1-147.8 (2003), and gr-qc/0306089) can be used to
create a toy "time machine" according to a number of published designs (see for
example I.D. Novikov, Sov.Phys.JETP 68, 439 (1989)). Assuming that such a toy
"time machine" does not work, a general prediction can be made of strong
electromagnetic field enhancement inside an arbitrarily-shaped nanohole near an
arising effective event horizon, which is supposed to prevent the toy "time
machine" from being operational. This general result is useful in description
of the nonlinear optical behavior of random nanoholes in metal films.
