Hi Zelda,
readmanic is a java app, and its quite nice: choice of colours, font sizes. It also supports zipped text which saves on storage space!
It can either be built (on a host pc) with embedded books, or it can use the phone's filesystem.
Its here:
http://www.deep-shadows.com/hax/ReadManiac/index.htm
It is annoying as you have to press OK to allow every file access (thanks to java security - as its an unsigned app) which means pressing ok about eight times as it loads.
Given the screen size it is a bit hard on the eyes - but its a great fallback if I get stuck with fifteen minutes to wait somewhere and I can catch up on a spot of reading!