Since each student has a Google account, I like to use Google spreadsheets with the students when covering the Central Tendency unit. Students share with me and each other the data that they've collected. Google Forms would be nice to use with the students - for example, surveying the students to verify that mastery has been met.
If my team and I were working on a file where collaboration was needed, I would use Google Docs. For sharing completed documents, I would used our shared folder on Dropbox.
I also use LiveBinders.com to store and organize media (pdf, flipcharts, video, docs) by unit. This allows me to stay organized by keeping in one place all data related to a unit. LiveBinders can also be shared with others on your team.