There are several iOS apps that turn iPhones and iPads into document scanners, so why doesn't someone build a stand for iDevices that would allow them to replace dedicated scanners?
For example, take the Fujitsu ScanSnap SV600. It uses a camera on a floating head, built-in lighting, and software (say, from Evernote) to scan documents, books, etc. A stand for iOS devices with lighting and the proper software, could do the same thing but for a lot less cash. The SV600 costs around $900; an iOS scanning stand would probably be in the $50-100 range.
Feel free to take the idea and run with it. Just cut me in when you start making bucketloads of money from the invention.