It really, really bothers me that wireframes have evolved from being a prioritisation tool into a layout tool (disempowering UI designers in the process), so I’m happy to see an alternative like this—somewhat like Dan Brown’s Page Description Diagrams.
Eric uses some super-clever CSS to “wireframe up” a web page.
I wonder if this could be turned into a little bookmarklet?
Less wireframing, more prototyping.
A browser-based tool for creating HTML prototypes.
Here's another CSS framework for grids. It could prove to be very useful for wireframing.