Developed by Paul Holliday, Gridmaker is a free plugin to create grid layers within Photoshop CS4. Gridmaker offers almost the same functionalities as Grid Designer apart from grid export to CSS. With real-time grid formation (online only) and export to a PNG, this utility is quite handy for web layouts.
In my tests the online version appears to be more flexible as Photoshop plugin simply adds a new layer every time you update grid and render it. The best way to work with this tool is to layout grid online and exports it as PNG to use in Photoshop.
This visual grid editor based on blueprint CSS appears to be the most advance grid solution yet. Built by Quentin T with Adobe Air, the application has a very simple interface to layout grid with PNG and CSS export. You can in fact create a basic HTML structure in Boks and it generates the script for you.
It handles grid configuration, baseline rhythm pimpin’, CSS (with or without compression) and grid.png export, HTML layout and much more goodie-goodie!