Much to the amazement of some people this thread is not about java.
I mentioned patience. The other thing I really value and cannot do without are amiable companions. People that understand that running rivers is a team sport, that we share the work load, wait for each other and stay in good spirits. I like my brother, my dog and really only a handful of tested friends for longer trips. They make the trip as much as the scenery, the wildlife, the whitewater and everything else.