Take a quick break and play the Accordion.
Re-size your browser to make some beautiful music; the kid in you will love it!

I want to play all the buttons at the same time and I can't, what I do get is quite effective.

That's really fun. Would be nice to have two mice (is the plural of computer mouse, mouses?), one in each hand, to click more than one button at a time. Yes, I know, it wouldn't work ....