I recently wanted to give my old iPod to my daughter's friend and ran into some unique problems because of the cloud. The first one was with my Appstore. Since my device was setup with the iTunes store for downloads, I could not disconnect that. Second, I had all my emails being downloaded by my Gmail App. The third problem that I encountered was in deleting my pictures and videos. It was not possible to eliminate them from the device with out deleting the originals.
How did we get here? With device independence using cloud based computing, it is possible to connect different devices to the cloud and replicate the exact set of applications and environments that you like. The good thing about this is that you can lose devices but still replicate your environments. The bad news is that it create extreme dependency to your devices.
Device independence should be a two way street. Just as you can upload information onto a device, we should also be able to disengage the device from the cloud -- zap all the custom information from the device. The big concern I have is that with a few bits of information, anyone can configure a device to replicate your environment.
Wonder how others have dealt with this problem dealing with their devices on the cloud.