This is not a terribly serious question, but it occured to me that "brief" or "long" are the only two ways I can describe the duration of a lucid dream.

Has anyone developed a system of measuring the duration of their LD? (dreamseconds, for example?) I am not referring here to how long you were dreaming for in "real time", but rather to how long you were flying around the forest for, etc.

Any ideas?