Adobe e-books are not supported, but note that Adobe Digital Editions (which does read them) is supposed to have a Linux version this year. That does not necessarily mean it will run on the N8X0 though.

It is embarrassingly easy to break the DRM of "secure" .LIT (MS Reader) e-books, e.g. using ConvertLIT. Use ConvertLIT to "explode" the .lit to a directory containing the corresponding OEB e-book (with a .opf file). FBReader can read the book starting from the .opf file, but the usual approach is to create a .zip file of the directory (renamed .oebzip) which FBReader will recognize as a zipped OEB e-book. So you start with a secure .lit and end up with a DRM-free .oebzip. If you have devices without both .lit and FBReader support, the OEB file can be converted to DRM-free MobiPocket using mobigen (again start from the .opf). FBReader can read the .mobi file, and MobPocket has reader software for a wide range of devices.

RTF and Text do not render correctly in FBReader (at least the version for the N800).

HTML works very well, but FBReader does not support all the tags and takes a liberal hand at the formatting.

You can convert txt to Plucker, which Fbreader does support well.

If you have suggestions about how to change the level of liberty , please share them at FBReader Google Groups.

Thank you everyone for the comments. Now a stupid question...

How do I download a book? I clicked and downloaded to my PC and copied it over to my N770. It says the file has unrecognized format (I picked the one said Plucker with Palm format).

Could someone show me a step by step guide to downloading a book?

Thanks...

Open FBReader.
Click on the single book icon with the + sign.
Navigate to where you put your new book on your 770 and have FBReader open it.

That's about it.

If you are not used to Linux, FBReader's file navigation screen can be confusing. It will only show directories and e-books (i.e. files it can open and read). Your MMC card will be something like /media/mmc1 and you select the ".." directory to get nearer to the root, "/", of the filesystem. Once you get to your primary books directory, FBReader will remember where you are for next time.

There is a tour of FBReader on the N770 in the screenshots at http://www.fbreader.org/screenshots.php

FBReader should work "as is", but if you read a lot of books you may want to take advantage of its extensive customization options. There are more details in the screenshots, or just experiment with the options.

Great! I got it now. Thanks guys.