Well - that was exactly the reason I did buy the PRS-505 eBook reader.
I have even downloaded all parts with are opensource. Still waiting to see if Sony will provide me the Sourcecode of the actuall build-package, so I can write my own Webinterface (It's nothing else than a WebBrowser accessing the local system which is running on it), and then I could at last do some changes I want, have the layout I want etc.

Whatever freaks do ...