Allowing the user to resize an element - e.g. shrink an img, or stretch a textarea - is a very common problem on the web, and it currently takes mountains of javascript.
HTML5 already has a "draggable" attribute, can we add a "resizable" attribute too? For example, <img resizable="all"> for an image that could be resized in any direction by the user. The browser would present an appropriate user interface.