I haven't tracked down the banking details, but there is a story that a major UK bank is planning a serious change in recommendations for their online banking. They are planning to distribute CDs at the bank, and ask that online banking users reboot from these CDs before performing financial transactions. The CDs will be a stripped down version of Ubuntu plus Firefox.
This may be inconvenient, but it does deal with the major security problem for most online financial work. The security geeks have been making the usual streetlight mistake. The easy and interesting problems of encryption and authentication have been engineered into massive bank vault level security. But they make the assumption that the underlying platform can be trusted. This is an absurd assumption. The huge market in virus scanners, and widespread malware infections demonstrate the untrustworthiness of most platforms.
The bootable live CD has considerably better robustness, at the cost of inconveniences. Each boot brings in a fresh copy of the software. Most malware infection cannot persist across a reboot, and it's much harder to infect in the first place because only the temp directories are writable. The only malware that can persist is one that manages to replace the hardware boot functions. This can be done, but it's rather difficult, and would still then need to be customized to specific characteristics of the CD.
The inconveniences are probably worth it for any small business or substantial financial activities. A hybrid system that requires use of the authentication from the liveCD to perform a financial transfer, but allows much wider access for financial reporting, would be acceptable for many people. It does mean that you reboot for some purposes, and that's an acceptable price for proper authentication of significant money amounts.
The regular system might still have key loggers, transaction interceptors, password sniffers, and all the other malware that assists in financial fraud. The fraud is blocked. It even fits the human factors better. It can be hard to make people pay attention to all the little details like "Don't click on attachments". It's easier to say "you must reboot and use this CD for making financial transactions with this bank". That CD is useless for other purposes. This is easier to learn and remember. It's also an easier mental model to think "secure CD for bank transaction".
I don't expect this to be nearly as popular with the typical consumer. The notion of reboot to do banking is seriously inconvenient. I do expect that small businesses with accountants and accounting clerks could adapt fairly easily, if there is a simple and safe way to transfer transactions between the internal accounting systems and the banking system. The story that I heard did not get into that level of detail.