One tip can could be useful to some is a trick to encode data into a "data:" url to encode all the information into one long URL. This allows you to access the URL on your iPhone even when not internet-connected. This can work for simple web applications, or even large PDF files.
Pimm describes how he used the URI Kitchen encoder to convert a PDF to be stored into a URL.
The recommended method to get this url into your iPhone is to bookmark it in your desktop Safari and allow iTunes to sync the URL to your iPhone.