Prebuilt is a simple red and white theme for WordPress. It has a top menu bar, relatively wide right side bar and an extended footer with Flickr integration.

From the site:

Prebuilt was created not to be heavily graphical and feature a lot of ajax goodness, but to be effective while at the same time, an easy way of learning Wordpress.

From the site:

Ambiru is a calm, reassuring theme developed for WordPress.

Ambiru is an unique single column theme with a header image.

If..Else Log is having a theme-a-day marathon and I thought of putting them up here. Here is the first. This is a simple 2 column site with plenty of white space with prominence to your content.

From the site:

Simpla is a clean yet aesthetically pleasing theme that will allow you to showcase your words without distractions.

Gespaa is a single column blue gray theme.

From the site:

Gespaa is an attractive, smart theme that was originally designed for private use on this very blog.

From the site:

It’s a black theme for minimalists.