Check out inudge the cool music creation site/tool. This is the first tune I created with inudge
OBTW you can also edit this and all inudge embeds of others creations, Very Cool
To edit just click the play button in the lower right
then click the colored sqaures on the right, to choose the instrument, then click the grid to creat notes.
Quote from their website
"Nudge is a virtual-instrument widget designed for self-expressive online music making & sharing. It’s fun and simple to use and you don’t need to know a single thing about producing music to make your own individual songs in minutes! Brought to you by the developers of the Audiotool, nudge is yet another example of the pioneering work of the team dedicated to creating the best online music production tools."