WikiComposer

An easy-to-use music composition software using the MIDI file format. WikiComposer is a music composition application that seeks to minimize the amount of friction that exists between the user's musical ideas and capturing those ideas.

It supports external MIDI devices, and takes a strictly what-you-see-is-what-you-hear approach to interface design.

Many of the operations you are familiar through word processors will also be available.

Notes may be highlighted by dragging the mouse over them. Such notes may then be altered in a variety of ways:
Highlighted notes can be copy-and-pasted by pressing Control-C, then Control-V.
Or cut-and-pasted by pressing Control-X, then Control-V.
Or deleted by pressing the Delete key.
They may be moved by holding down the Control key, and then pressing the arrow keys.
Their dynamics can be altered by holding down the V key, while moving the mouse up and down.
Many (but not all) operations may be reversed by pressing Control-Z (Undo).

Limitations:
Limits the size of saved files