I have been helping my daughter over the phone with first year physics and have run into a problem with communication(insert your favorite joke here). It is difficult to describe a diagram that has vector, angles, notations and also associated equations. I would like to be able to freehand sketch a drawing or write an equation that would appear real time on her computer screen or alternatively could be written on a digital sheet of paper that could be easily and quickly sent as an email attachment or in some other manner. Has anyone here had this situation before and know of some relatively inexpensive solutions. Any ideas would be greatly appreciated. We both use Mac's. I have looked at Wacom's Bamboo Pen as an input device but have not tried it yet.