Use plugins to allow user configuration of modes

For "screen saver" or "display while playing audio" (maybe others), allow a plugin to be run.

I suppose the plugin then needs to be interruptible somehow, and maybe needs to meet certain criteria (you probably wouldn't want a plugin that is statically displaying data for a screen saver, and you wouldn't one that plays audio for music.)

Perhaps a plugin could "register" the criteria it meets (interruptible, dynamic display, silent mode) and then when you select what plugin you want to define for that function, you'll get a list of plugins that meet the spec.

Maybe the plugin could have some kind of callback where it could sample data from the calling function to know what's going on. For example, if called from a music program like jukebox or the built-in music player, it could callback for the currently playing title.

I specifically would like to be able to have a clock with the local weather as a screen saver, bouncing around and changing colors, maybe displaying the current title/track of any music playing if run from a music player.