Graphpaper Press is Thad Allender's repository of minimal themes for WordPress that are built on the Blueprint CSS framework. Allender is creating 1 new skin every month in 2008. The first in the series are the Gridline themes, a pared down, minimal design that comes in three flavors: lite, news, and magazine. Any of these should provide a barebones framework for a small business looking to use WordPress to get their site up and running quickly. From the base stylesheet you can tweak CSS to suit your brand.
Of course, the danger in using themes like this out of the box is that your site ends up looking like scores of others. Most of these look like Subtraction with subtle variations and added content modules, so take the time to customize the theme.
You can find more info about Graphpaper Press themes here.