Reshared post from +Phil Ames
The list of sites is depressingly small.
On a more positive note, though, I just registered for something yesterday which allowed me to link an OpenId identity so I could force authentication through my 2-factor enabled Google account.
Turn On Two-Factor Authentication on Sites You Use
Cloud storage provider Dropbox enabled two-factor authentication on its accounts very recently, and I finally got around to enabling it on my account today. I also decided to see what other cloud serv…
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