Hiding a mini fridge at your desk isn't really very difficult at all. All you have to do is keep one of your filing cabinet drawers reserved to put it in.The other alternative is to keep it in the section reserved for your legs, but cover it up with a rolling file or a printer stand or something.
You can have cold pop all day long (or something different of course...just don't burp in anybody's face) and cold snacks too. You will be safe in your cubicle walls from prying eyes to eat and drink and be merry all through the day.