Getting rid of pond snails

A number of posts in the past, plus one in the most recent List, mention
problems getting rid of pond snails.  They are just about the favorite food
of Figure 8 puffers!  These little guys are happiest in brackish to full
strength sea water, but are most commonly shipped to such places as Wal-Mart
in plain old fresh water.  As I say, pond snails are really ice cream to
them.  Has anyone on the List tried these quaint little guys? They swim like
little helicopters. (BITE the heck out of other fish, also your fingers -
they seem to have no fear!)