1. A computer program product for controlling a computer to execute a computer program within a computer memory, said computer program product comprising: (a) a loader program; and (b) an encrypted version of said computer program; wherein said loader program is operable to: (i) read said encrypted version of said computer program stored in a program store; (ii) decrypt said encrypted version of said computer program to form said computer program in an executable form; (iii) load said computer program directly into said computer memory; and (iv) trigger execution of said computer program as loaded into said computer memory by said loader program.