Today, I found out about a WordPress plugin called Elastic (http://elastictheme.org/, download link) which is a WYSIWYG theme editor for WordPress.
It looks like a very promising technology to make it easier to develop WordPress themes. I’m interested in re-useable modules so, if I develop something interesting for one client, I can re-use the same something for a different client with 1-click (therefore being able to quote them a reduced price). Plugins and widgets achieve this to some extent but Elastic aims to make the same possible at a more fundamental level.