This is a very, very, very simple proof of concept program for Windows. Roark is a web layout tool that lets you draw and rearrange divs and then save your layout as regular HTML. Support for CSS frameworks such as Blueprint is expected in the near future.
Currently there is only a version available for Windows but a Mac version may eventually be released. You will need the .NET 3.5 runtime if you don't already have it installed. Follow the second link to download that.
Downloads:This video isn't the best quality and doesn't show a lot of detail, but it should give you a feel for what Roark does. Also, the audio lags the video by about half a second or so, which is kind of weird.