Pressed Key effect
The most useful effect by far is the pressed key one: with the whole keyboard with one, fixed color, once you press a key, it changes to a selected color, then slowly (adjustable) changes back to its original color.
Rather than looking pretty, this is ideal to realize whether you've hit one or two keys when your aim isn't all there. Or, you can always give me some pointers on how to code an effect, and I'll gladly do it.
Cheers!
@SammyKat I would love to write that effect, but it is not easy, as it would require the service detecting keyboard strokes all the time and recognising them under different keyboard layouts. I will try it one day but I am afraid it won't be now. Cheers.