how about TheWorld Browser can it be a portable

It is not open source - in fact, it has one of the oddest licences I've seen

It is free for non-commercial home use.... OK so far.... but there is no other option. I can't even see a way of buying it for other uses.

And it strikes me as rather funny, that someone with a fire bird for a logo uses an IE based renderer

But the fact that the licence is so closed off means that it probably won't be happening here