You can download from here a simulation of the worlds first computer game.
A version of noughts and crosses, this was created on the EDSAC comuter in Cambridge, which first ran in May 1949 and was probably the first stored-programme computer to actually perform regular work.
As there was only one machine which could run it, the game did not achieve wide a wide user base. EDSAC istelf was hardly portable. One of its first serious uses was to discover the largest prime number then known (79 digits).