The most obvious answer would be plucker and Vade Mecum:
The PC-based components:
http://desktop.plkr.org/downloads/msw/
or
http://laurens.typepad.com/ (I like this one better)
The PPC-based reader:
http://vade-mecum.sourceforge.net/
The main advantage of this over iSilo is that it is free. It is not as feature-rich, but may be good enough for your needs.