I work in a school environment.  The students have very limited rights
to everything on the local machine.  Some of the teachers have USB
"thumb" drives.  Certain ones, when plugged in with the student logged
in, work just fine.  Other thumb drives seem to try to install
software and give an error to the students that they don't have the
rights to add a device.  Does anyone know how I can tell for sure
before I buy it which way a thumb drive will behave?  I would like to
give a recommendation on what to purchase so they all work out of the
box.