Tableau is one of many applications that would benefit greatly from an Auto Save feature. It's been a much requested feature from Tableau users for years. While not built into the application directly, you can now have your Tableau workbook save automatically every X number of minutes using a third-party tool called AutoHotKey.
All the credit for this great find goes to Nelson Davis, a recent presenter at TCC13. For instructions on how to set up Tableau to Auto Save, check out this post on Nelson's blog: The Vizioneer.
By the way, Nelson also went to GA Tech, the school where "You can do that". Thanks to Nelson's Tableau auto save instructions and AutoHotKey, now all of us can do that.