Of all the applications for the iPhone, one of the ones that promises to be the most usefull is DataCase from veiosoft. As the video above demonstrates, DataCase will turn your iphone into a storage device for files of all types, including audio, video, pdfs etc.. Simply connect your iphone to your mac and drag and drop the files from iTunes. The files will now appear in the DataCase app, and clicking on them will activate the appropriate application.
We don't know much about the company, but this app is one that we will be looking forward to covering in the very near future.