In BBEdit, you can move the line of text that currently contains the cursor up and down with Control-↑ and Control-↓. If you wish to change the shortcut, go to Preferences > Menus & Shortcuts, and then choose Edit > Move Line Up/Down.
George Bray writes:
Another good reason Apple should get Cyberdog out quickly, simply, and inexpensively is to lure other platforms to OpenDoc. Apple has a one-shot chance at proving all the theories behind OpenDoc