Lesson

I, too, use the same lesson pages in multiple courses.  If there was one change that I wish for in Moodle right now, it would be that Lesson pages could be stored in a "bank", and used in multiple places, like a 'question bank' for quizzes.  The way it is now, if I find an edit is needed, then I have to make the change in many places, and keep track of it all...
Enough complaining -- Moodle is still great.

It is possible to use the Quiz Module to build something very much like lessons, as long as you don't need the 'branching' functions of the Lesson Mod.  The "Branch Table" page can be replaced by the "Description" in a Quiz.  However, this does NOT work for me because of differences in navigation, and scores being displayed, and several things that I just can't work around.  But you can look at that option...

As far as copying Lesson content, you can make duplicates of a Lesson pretty easily.  If you want to copy Lesson-A and change it slightly to become Lesson-B, it goes as follows:

• 'Backup' Lesson-A
• Rename Lesson-A to Lesson-B, and change it as necessary
• 'Restore' Lesson-A from the backup file

Hope this helps.  (And I hope sometime Lesson pages can be shared like Quiz questions...)

Dan