If you enjoy listening to music, we bet you'll love a music visualizer. VSXu Player "listens" (via recording the audio) to the music you play and visualizes it, regardless of music player*. It works with - iTunes, Spotify, Winamp and others.
This is what VSXu Player looks like in action:
Effects pulsate with the beat, or build slowly with the intensity of the song adding details on the higher frequencies (like cymbals) and you add an extra dimension to music listening.
You can change speed and intensity of each visualization, making it more fitting to the music playing. Player also ships with many different visualization designs, so there's surely one for you to fall in love with.
Since VSXu Player records via the default sound card mixer rather than being bound to any particular media player, you can also record from Line In. Connecting your computer to your TV and running VSXu is great for parties!
*Drivers on Windows coming from Microsoft generally don't support Stereo Mix/loopback recording. You might need to install your sound card vendor drivers.