Sometime you need to wait for the end of your command. I recently do kernel compilation alot, and I have to wait about 30 mins for each compilation. So I just run it background, and do other things. This is when you need a sound alert letting me know that the compile is done. Here’s how to.
time [yourcommand] && paplay [sound_file]
paplay must be installed in your system by default, and numerous system alert sounds can be found under /usr/share/sounds..
have fun~~ ^^