In addition, the next top 3 placers will each get a $50 American Express card or $50 donated, in their name, to the charity of their choice.
To earn points, just participate in the various event activities (go to sessions, post in the discussion forums, visit sponsors, etc.) and you’ll get a points code. Then, just go to the Mash-Up Attendee ShowDown section (use the right nav menu or go to it from your home page in the event app) and enter that code in the list of challenges provide there. For more information see our official rules page.