I have a client who wants to make an interactive CD to accompany a book. 
  By interactive I mean search, hyperlink, etc. content from the book, 
not like homestarrunner.com or pbskids.org or something.

The application isn't too complicated, and I'm likely going to do it in 
Ruby - maybe as a Rails app or maybe Camping, or if it's easy enough 
possibly some GUI toolkit. The question then is, can I have a standalone 
Ruby on the CD that will work on Windows without any install step? I'm 
not overly familiar with Ruby on Windows (or Windows in general). It 
would also be nice to have a static ruby that would work on linux x86, 
but I'm comfortable with a README that says "install Ruby" in it when 
push comes to shove. OS X (Tiger and up) has Ruby already. So Windows is 
the real question.

So I envision a .bat file (.sh on linux/osx) that fires up a local 
webserver (mongrel or webrick) and serves up a camping or rails app off 
the CD, accessing the data in SQLite, or perhaps just reading it in from 
a YAML or XML file (the data set is not huge).

I think this should be not-too-difficult, but I appeal to the group 
wisdom for any gotchas that I may not foresee.

Thanks