I sometimes use Mobipocket Reader on my Nokia N95 (you can use the landscape mode) but I prefer the audiobook player on this phone (you can download it from Nokia site). I listen to audiobooks while driving. It can store bookmarks and starts from the point where you last left. You can jump between books without losing your bookmarks. Must be the best audio book player around and it replaced my iPod after it finally died after 7 years of faithful everyday service. I am listening to Naxos Audio version of
Kafka on the Shore these days:
http://www.naxosaudiobooks.com/PAGES/40512.htm