ScriMan: Scribble Helper
ScriMan is a small web app that allows you to scribble directly in the browser.
Among other things, the app supports drawing with transparencies, layers of various colors, erasing, etc.
The work can then be saved as a PNG with transparencies as a whole or per layer.
The whole thing was created as a small task to learn Canvases and its possibilities... as always of course written in native PHP, HTML5, CSS and JavaScript without any form of external libraries.