I think with twilight.net it's an efiction archive?
when you're at a story that has multiple chapters if you add this code to the end of the url
?action=printable&textsize=0&sid=1&chapter=all
(You may have to change the sid number to match the sid number on the story you'd like a single file version for)
it should place all the chapters into a single file. I don't know why they don't have that activiated which makes me think that maybe it's not an efiction based archive.
I read RTF on my Sony PRS-505 all the time because it's the fastest method to get ebooks on my device. I would recommend BookIt plugin for Firefox (do a search on mobile read) however the select to LRF feature isn't working for some reason. But if it did work I imagine for single file LJ stories this would be handy.
For LJ I merge the fics using Word and then I have some macros that help me clean up the file and resize the text.
For stories I really like (and because I run the
Ebook Library) I do convert the stories to LRF/Epub/and Mobi.
I recommend you check out the LJ community fanfic_ebooks I have tutorials and screen caps of how I'm accomplishing this.
The short answer is I use Word 97 (that's Microsoft Office 97 from 1997 to be clear) I open the RTF in Word 97 and save as an HTML, then I copy the code into a Word 2007 document and run macros on it to clean up the code.
After I finish my last research paper I had planned to make a tutorial for macros.
Anyways, once I have the a clean version of HTML I import into Calibre and convert to LRF. At the LJ fanfic_ebooks community I have my settings listed and more exact details.