This is a really simple modification of an existing program found here. All I have done is included a system call to mplayer that loads a short 27 second .wav file of the nyan cat background music and loops it for as long as the program is running. Obviously this requires one to have the .wav file in the same directory as the binary, and to have mplayer installed. Alternatively, there is always the option to modify the source to call some other method of playing the audio file.
The argument passed to the nyancat binary to toggle the terminal title off was changed to -l so that the -s argument could be used for enabling the background music.
To rebuild the binary from the source just put the following into your terminal while in the directory containing the readme:
make && cd src
Then to start the program with sound:
An archive of the files necessary to experience the nyany awesomeness yourself can be downloaded here.
I initially debated whether or not to post this here, given it is such a trivial change, but decided I might as well since some one somewhere will be interested.