Binoculars are handy for initially locating fairly bright objects. This can help you point your telescope finder more easily. Some star clusters simply look better in binoculars than in a telescope. A small, portable camp table for your equipment and references can be very handy, as can a portable camp chair. If you expect to maintain a logbook of what you see, bring a piece of plastic to cover the paper to protect it from dew.
Soft pencils write better on damp paper than pens do.