Note
Great little program for viewing images of all kind, can read directly from archive-files. Thanks to bam from the oesf.org-forums we have an english translation. I've uploaded a modified ipkg for the english version to my feed. If you speak japanese you can also take a look at the original japanese page
eBook reader which supports a lot of formats among them chm, html, fb2, plucker… (see the FBReader page for more info and the newest version)
as the name suggests, a viewer for PDF-documents. It's a bit slow, but the only usable PDF-viewer for Cacko/SharpROM get it from the cacko feed