While searching around to see where else this might have been mentioned, I happened upon this page at the Google Help Center, with an even nicer answer -- just use https://mail.google.com/ as the URL, and you'll have a secure connection. I've been using Gmail for a long time, and had no idea they had a secure connection available (beyond the login screen), so I thought this worth sharing, even though it's documented. (And Dave's article pre-dates the "modified" date on the Google help entry, so it's possible that page didn't exist when Dave wrote his piece.)

