Not being able to set up a file and file folder system on my iPad is my one single largest GRIPE! Yes, I know there are some apps but they are all work arounds and do not let me exploit my 64gb of RAM that I purchased. Apple's failure to do this will always keep my iPad in the realm of a Internet appliance rather than a serious business device.
Seagate makes a wireless hard drive that will do what you want and I am sure that it will,store more info than you could ever want. It is not what I want to carry. I use DropBox but even it is crippled and will not work like it does on my computers and you must download a file before you can use it. DropBox is as close as it comes. Apple will not change and makes me still interested in the new Win8 tablets to arrive later this year.
I want more freedom from Apple and iTunes!
I need Microsoft office and some form of file manager. I need be free to upload my files online, download them and share them. Bluetooth and wifi should be able to take care of any file transfer and printing issues.
Even with options such as ifile we still need a change of plan from Apple so the apps themselves facilitate this.
I work in finance on our company network has multiple drives and folder full of spreadsheets and reports. If the iPad was able to access these networks and act as a functional client then it could easily replace the millions of Wintel PCs in businesses.
I have high hopes that Tim Cook will start steering Apple in a more business friendly direction.