I do most of my reading on my various handhelds and recently acquired some new hardware. E-book reading ont hese devices is a real pain. I really like Microsoft's LIT format but the reader really sucks. It does nto support anything else besides LIT books and requires activation (that sometimes doesn't work) to read DRM'd book (DRM sucks anyway -- but its the world we live in). So I have moved over to uBook Reader (much nicer and support lots of formats). Only problem is I have ton of .LIT e-books. I used a command-line program a while back called convertlit. It was pretty good... but it was command line and a little cludgy to use. Since then a guy made a GUI for it which looks pretty good. I also stumbled across another free converter that ALSO looks pretty good and seems to have more flexibility and export formats. Heres the links to both:

http://www.processtext.com/abclit.html
http://dukelupus.pri.ee/convertlit.php