1. A method of executing one or more virtual applications from a single executable file, the method comprising: receiving a character string comprising a first parameter, a second parameter, and an identification of an executable file implementing a plurality of virtual applications, the executable file comprising a plurality of startup files each corresponding to one of the plurality of virtual applications; executing a process of the executable file; determining whether the executing process is a first process of the executable file to be executed based on presence or absence of a data structure associated with the executable file in a shared memory; allocating a data structure in a shared memory associated with the executing process; passing at least a portion of the character string to the executing process when the executing process is determined not to be the first process; and when the executing process is determined to be the first process, parsing the character string to obtain the first and second parameters, identifying a particular one of the plurality of startup files, and executing the particular startup file, wherein identifying the particular startup file comprises: determining the second parameter is a candidate trigger when the first parameter has a predetermined format, determining one of the plurality of startup files associated with the candidate trigger is the particular startup file when the candidate trigger is a member of a triggers list, and determining a predetermined one of the plurality of startup files is the particular startup file when the candidate trigger is not a member of the triggers list.