Just to clarify: I do not want to convert the HTML, I want the Kindle browser to open HTML that I've copied to it. So I need to know what file://.. path to give to the browser to open something from its own file system. I've looked for information on the various kindle hacking blogs but haven't found it yet. But I know that somebody knows!
Of course one can put the HTML on a web server and point Kindle browser at that instead, but I was just curious if it is also possible to point it at its local file system also, just as every other browser I've ever used lets you do.
One reason behind my curiosity is that I want to get some idea of what kind of user experience can be delivered on Kindle with JavaScript-enabled content. Ideally, being able to open a local file would eliminate overhead of a relatively slow wireless network (yes, I know about the network-over-USB hack, which should be much faster than wireless also). While AZW does not currently allow for scripting of any kind, some future version might (it is part of the OPS spec which most ebook formats are based on).