Is there a desktop wallet client that uses two factor authentication? I know it's an extra step of paranoid, but, well, that seems not entirely unjustified. I googled, but to no avail... too hard to filter out the online wallets with 2FA.
There are plans to implement 2FA support into Electrum. Not available yet.
That's great news indeed for us paranoid folks! I'll be jumping on this update for sure.