https://github.com/jdg/MBProgressHUD
http://cocoawithlove.com/2009/04/showing-message-over-iphone-keyboard.html
http://www.developers-life.com/custom-uiactivityindicatorview.html
http://www.youtube.com/watch?v=1vWpUwz_xy4
http://iphonedevelopertips.com/user-interface/uialertview-without-buttons-please-wait-dialog.html