I'm on a roll with shelving systems for the vertical desk setup. I'd declare a shelving week as I did for mobile desks before but I don't think I can find enough of them for a week!
ISS Design's shelf system is interesting. They have shelf standards for wall mount, and for freestanding, which fastens to the ceiling or braces back to the wall. You would have to choose which configuration you prefer, and there are some considerations for both.
Lets look at wall mount first. The good news is they have a rectangular bar shelf support. This means you can roll a mobile desk under it without a concern about hitting into a triangular shelf support. They make those as well, but the rectangular bars are a better match for use with a mobile desk. Their standard brackets come only 16" deep in the largest size. With a little overhang you could mate this with an 18" deep shelf to be the desk height surface. A little shallow, but enough for todays flat screens. They also make a heavy duty bracket which comes up to 24" deep. This is the perfect size, but the bracket is 3/4" deeper than the standard bracket. No problem, just a little bit more height difference between your mobile desk and deep shelf.
They also make freestanding poles. Now if you were to use these you would combine a fairly short bracket, say 6" between the pole and the wall, and a deep bracket cantilevering out to the room, say 16" to make a total work surface depth of 24". The only trade-off here is your mobile desk can only roll under as far as the poles. This will increase the minimum distance you can get between the front of your mobile desk and your screen if you are using it for your computer station. Just something to keep in mind if you are the type to put your face in your screen.
They are quite flexible and it really makes a handsome set of shelves. Perfect if you desire something that looks more finished than the Ikea Broder or E-Z Shelving systems.