M-Audio O2
The M-Audio O2 is a great travel companion. It has real size keys but is super slim. It even has assignable controls so you are in charge of the Reason rack devices. I am testing Apple's own Garageband right now and it is fun. :-)The best thing about the O2 is of course that it is super tiny: it fits in every suitcase so I can take it with where ever I go.