The best PocketPC book reader (and freeware as well) IMHO is ubookreader which you can download from
www.gowerpoint.com . Among its many features, it allows you to read HTM, RTF, TXT, PDB and PRC, supports different fonts, has a great autoscroll, and also reads books through .zip files *saves space, I'll tell you! particularly if you've got 20 to 30 or more books on your CF/SD card all at once.*