While I can’t imagine Siddhartha on my PDA (well, I don’t actually own a PDA but whatever), I’m sure someone would enjoy it. If that person is you, you might want to check out manybooks.net–a site which contains more than 10,000 free ebooks (free, I’m assuming, because they are past copyright). It’s a nice, easy to use site which also features ebooks in many different languages including: Esperanto, Latin, Portugese, Swedish and Tagalog.