In Windows, is there a simple way (i.e. something you could type on a single command line) to just play a couple of .mp3 files and then exit on its own?
wmplayer, f
You can use fmedia to play audio files from Windows terminal:
fmedia file1.mp3 file2.mp3
This command will start the playback of file.mp3, then file2.mp3, and then quit after the files have finished playing.
If you wish to do it in background, add --background switch to your command:
fmedia file.ogg --background
This command will start a new process in background and detach from your console immediately.
fmedia is a portable application (works without installation) and consumes very small amount of system resources. Also, its startup time is instantaneous.
P.S. Use command fmedia.exe --install to add it to your %PATH% environment variable, otherwise you need to execute it with full path, e.g. D:\fmedia\fmedia.exe