Crazy, I hadn't appreciated that.

So:

  Fn-Left = scroll to top
  Fn-Right = scroll to bottom
  Fn-Up = scroll page up
  Fn-Down = scroll page down

  ⌘-Up = cursor to top
  ⌘-Down = cursor to bottom
  ⌘-Left = cursor to start of line
  ⌘-Right = cursor to end of line