It would be nice, if we have a Command Turtle and a Command Pocket Computer.

This was suggested a while back on the forums, and I'm still not sure how useful they'd be. Command computers are very much intended as a creative adminy thing, so don't have much utility as turtles/pocket computers.

Considering that you'd have to be opped and in creative mode to use them, they would hardly be much more useful than placed command computers