I think many of us have had the experience of needing to send a file that is just too large. This is a free service that does it for you. I found this very helpful when I needed to send out an eLearning module that was just too big (even when zipped).
After using this tool in my internship at Cricket and in creating learning interventions for Marcie's class, I have found that it is truly a versatile and easy-to-learn too. I suggest you check out the free 30-day trial.
I love using this to create lessons that my students can interact with. If the students I work with were slightly older I would definitely have them use it to create interactive posters too.