…and on a Mac, to delete to the start of the line, type CMD + backspace. I started using this shortcut, and the parent one, about two weeks ago. They are just now becoming muscle memory, and I find them very useful.
FYI, in OSX a lot of emacs/shell shortcuts work in textboxes/-fields too. e.g., ctrl-a, ctrl-e, and ctrl-k respectively for beginning of line, end of line and deleting to end of line.