Smile / Co-op does online banking very well. They have generally good customer service, and you can do the physical bits by going to a Post Office or Co-op shop, and withdraw cash from just about any cash machine (specifically, they're in the Link network). I don't think they're as "ethical" as they claim to be, and they are not very good for anything more complicated than just holding a current account with them. I've had a vanilla current account with them for, oh, 9 years now (since Lloyds pissed me off). I have never had a serious problem with them, and they have been helpful and prompt in sorting out minor problems.

The caveat is that I've mostly been using Firefox under Windows; I can't absolutely promise you that their system will work with more obscure browsers / OSs. Also, they do insist on that annoying "Verified by Visa" thing for online shopping; it's pretty hard to get out of that these days, but if that's a big principle thing for you, Smile won't work.