How does one empty the ENTIRE shopping cart? I'm finding having to delete each product in the cart one at a time to be very tedious.
That's currently the only way.
(grumble) (grumble) ~_~
Or you could put a "0" quantity for the first item in your sidecart, then hit the tab key (that should bring you to the quantity field of the second item), put "0" again, hit tab, etc., all the way down the bottom of the list.
Then use the "Update Quantities" button. If you have a keyboard, this should definitely be faster than removing the items one by one.