WYSIWYG Paint or Sound
I suggest a WYSIWYG editor for drawings and a WYSIWYG editor for melodies that are similar to XPaint and KWave. Some kind of Java Applet or Macromedia SWF program so we are capable of adding drawings and melodies quickly. Or maybe it would be nice, to play some melody with the keyboard ("a" = C1, "s" = D1, "d" = E1, "w" = C1#, "e" = D1# ...), which can be recorded immediately (as MIDI).
I would be glad if such a WYSIWYG editor was possible to program without plugin, but I do not believe there is an acceptable HTML-based solution.
So we create eg a Java Applet. This applet is loaded into the browser if you add some special markup-tags. There you can draw something and afterwards you click on save. The image is sent to a database; and if visit the page, you see the image without plugin. Then there is a special tab "edit" on the top of the picture and you can click on this tab. Then a window with the Java Applet editor appears with the latest version of the picture and you can edit it again.
Yes, I know. There are several browsers that are neither capable of Java nor capable of Flash.
I do not have anything ready yet, but I would agree to contribute to WikiMedia under GPL. If somebody else thinks such a WYSIWYG editor would be usefull, please send an eMail to hgzojer#yahoo.com and let me know.