1. A method of operating an application attaching system to dynamically make applications available to a computing device, the method comprising: identifying an application attach triggering event based on a file selection of a certain file type on the computing device; in response to the application attach triggering event, identifying an application within an application volume based on the certain file type; attaching the application volume to the computing device, wherein attaching the application volume to the computing device comprises mounting the application volume to the computing device and modifying one or more registry keys on the computing device to make the application executable from the application volume; associating the application to the certain file type on the computing device; executing files for the application stored on the application volume to support the file selection; identifying a detach triggering event; and in response to the detach triggering event, detaching the application volume from the computing device.