I didn't find any online collaborative projects that applied to drama--not surprising. I'm sure there are projects out there. I will keep digging.
Education World has some Readers Theater scripts (like Cinderella), but they are geared for a younger age. http://www.educationworld.com/a_curr/reading/ReadersTheater/ReadersTheater001.shtml It would be fun to use these scripts for a young audience either live or online. Bear Boulevard loves to come to our fall musicals, so I'm sure we would have a willing audience.
And as soon as I have the right computer, I would like to use Skype. I would love to contact performers that could tell students about their journey to the stage.