Hi Geert
The Alpha Base Station is not sold with rack ears as it is not intended to be rack mounted - it has the pedal inputs (for 2 continuous control pedals and 2 switch pedals) and is usually sited near your home playing position on stage as a result of this. When you experience the Alpha, you will really want to use those pedals. It also has a MIDI in/out so that you can connect a MIDI pedalboard to it, to give yourself even more switch options (though the MIDI i/o is not due to be functional until mid January 2010) and an extender socket so two base stations can give you a greater wire length on stage and remove mains power from anywhere near your playing position, an important safety improvement if there is any possibility of moisture in the environment. This will allow you site an extra base station in a rack somewhere, near whatever computer you choose to run as well, without losing the pedal inputs on a larger statge.
I believe it is the right thickness to fit in a 1 U space should you really wish to rack mount it, although due to the pedal inputs you'd probably want to do it back to front and you'd have to unscrew its rubber feet. I'll check this out for you. It is also just the right size to velcro a Mac Mini to the top, if you want to play without using a screen at all (and we have really interesting development going on that will make this an attractive possibility shortly) - this would give you a very nice compact kit for playing with a very short setup time. We've experimented with running EigenD headless (without a screen) in performance and it works well.
John