This template is now being maintained at Konigi. Please download there.
I created an Adobe Illustrator template for creating comps that work with Olav Bjorkoy's Blueprint CSS Framework.
The Illustrator template is simply a document with guides based on the 24 units provided by Blueprint. A layer is provided to show unit numbers if you like, and 2 layers showing the grid dividing into thirds and quarters (thanks to Phil for that). Additionally there is a page wireframe included to demonstrate the template's use. Enjoy!