The Motorola Droid has a "smart dock" that will put the phone into an alarm clock mode, as well as a car dock that will automatically launch the navagator application. It might be possible to do something similar with a Maemo device using the micro USB port.
Since the word on the N900 USB is that there is no way to put the port into host mode, this may have to wait for the next hardware design. However, it would be useful to build in pnp support. As we've seen from the Palm Pre spoofing an iPod, there is a standard database of codes used to identify devices. This could be used in a similar manner as with the Droid to change mode to an "alarm clock" or similar application. There may be some interest in a car dock that could set up navagation and media player applications.
It may also be possible to introduce docks for high-quality audio (Toslink), wired networking, or a full PC style docking station with keyboard, mouse and display (would need to use the video out port, as the usb interface isn't going to be fast enough). By buillding PNP support into the OS, a standard wired I/O could be developed as a framework for future use.
