libprs500 0.4.1 has an open source cross-platform LRF viewer that supports hyphenation (for english) and uses real fonts instead of the SONY's limited three. Use it from the command line (for the moment) by
Note that this is an initial implementation and so its bound to be buggy. I've only tested it with LRF files generated by recent versions of libprs500. Also the current implementation is slow/memory intensive, so I doubt its suitable for use on handhelds. I will work on speeding it up when I get the time.
It doesn't support the DrawChar tag as yet (Used to make drop-caps) and the search functionality is not implemented.