Bumping this again as I think this should be implemented before a year from now.
If someone wants to write a patch for it, I will seriously consider adding it. I believe that safely adding 2FA would be very time-consuming, so I'm not willing to do it myself or direct Slickage to do it.
Not sure how time consuming this would be, I'm willing to put 1
BTC towards a bounty for it though. The only condition of the bounty would be that it is of high enough quality to be accepted/implemented by Theymos. If anyone would like to contribute towards this bounty or is interested in writing the patch please let me know.
EDIT: I've doubled the bounty if anyone is interested, it is now 2BTC.