On the "inconvenient/risks" point - yeah, security is pretty much always a trade-off between convenience and risk. I've already chosen two factor auth for gmail (and Amazon and Dropbox, and I'll add any other important service I can to that list when available), so I pretty much need access to one of my two phones or my iPad to run the TOPT token generator - and if I have any of those devices there's clearly no need to me to trust a borrowed device.
(Though in the complete disaster scenario, I have stored in my wallet, as suggested by Bruce Schenier, the app-password my phones use and the list of backup verification codes - unlabelled so a casual thief _probably_ won't know what to do with them... I've also got irregular exports of everything and the 1Password passphrase and phone PIN printed out and stored in an envelope in the office safe. I _think_ I'm sufficiently paranoid about all that...)
(Though in the complete disaster scenario, I have stored in my wallet, as suggested by Bruce Schenier, the app-password my phones use and the list of backup verification codes - unlabelled so a casual thief _probably_ won't know what to do with them... I've also got irregular exports of everything and the 1Password passphrase and phone PIN printed out and stored in an envelope in the office safe. I _think_ I'm sufficiently paranoid about all that...)