If you have to jointly author a spreadsheet with a colleague, what is the first thing that you do? Email it back and forth. This can be painful, particularly as you try to keep track of your partner’s changes and hope the emails transit back and forth across the Internet. Add a third or fourth person, and things get worse. Luckily, there is a better way, and a number of providers have stepped up with tools to make spreadsheet sharing a lot easier than sending attachments.