A system for providing computing capacity includes a base module and two or more fin modules coupled to the base module. At least one of the fin modules includes one or more fins and two or more computer systems coupled to the fins. At least one of the fins to which the computer systems are coupled extends from the base module such that the fin has a primarily vertical orientation. An electrical power bus in the base module supplies power to computer systems of the fin modules. The site of operation may be indoors, out of doors, or in a limited shelter.