I love pie menus. The stock Android Browser's hidden "quick controls" are incredible and by far the fastest way to use a mobile web browser. You slide your thumb in off the side of the screen and then in the same motion move to the action you're looking for and simply release to activate. It's not obvious unless you show the user it's there but once you have it you don't want to go back.

link for the curious: http://www.droid-life.com/2012/02/07/tip-browser-quick-contr...