After getting hooked on palm eReader on my old palm device, once that became obsolete I looked around at alternatives, long story short I now use FBReader on my laptop it's open source and supports the open .epub ebook format and pretty much all others, if i can't find a ebook in the format it supports there are many tools around for converting to .epub or another supported format link - http://www.fbreader.org/

thought it might possibly be useful to see the actual website for the product http://www.adamobydell.co.uk/