We're here at beautiful Fort Mason, with San Francisco Bay and the Golden Gate Bridge as our backdrops, and Engadget Expand is about to kick off! We couldn't be more thrilled about this weekend's lineup, which includes fireside chats with innovators from Google, Kickstarter, OUYA and more -- not to mention our first-annual Insert Coin competition and -- wait for it -- Tesla Model S test drives. If you haven't purchased tickets in advance, don'