WP Plasmashot

Two columns, widget ready, left side bar WordPress theme.

miniBlog

Simple two column white and grey theme

OneNews

Turn WordPress into your personalized news aggregator.

Teal

Simple two color theme made up of two colors, teal and white.

AcosminTECH

Three column, widget, gravatar and ad ready theme

mts Journey

A classic 3column, widgetready, gettexted and flexible width theme that supports print and PDAs.

Ocular Professor

Ocular Professor (OP) is a WordPress theme designed expressly for photobloggers. Designed to incorporate the new gallery features of WP 2.5+, OP also includes a widget-enabled footer; a “Featured Post” section that, when enabled, allows posts to sit outside the normal flow of blog posts; special formatting, such as drop-caps and image captions; and author comment highlighting.

Dust

A fluid three column outfit with a header image rotator built in: widgetized sidebar and footer columns, built in are recent comments with gravatars, related posts, social bookmarking enabled. Delicio bookmarks, Twitter and Flickr is enabled in the themes options panel.

Brown Stitch

2 columns theme with widget ready on right sidebar. The bottom 3 columns were fixed though.

Notepad Chaos

The theme has 2 columns, a quite vibrant design including “personal” design elements such as handwritten headings, stick-it-notes, clips and pins.

WhiteWash

A fast loading theme without distractions, images and cluttering. WhiteWash is easy to customize and it’s ideal for users who don’t want a blog with many colors or stuffed with features. Because of the wide spaces, this Theme is easy to read. Image-styling, when a picture is linked with a larger image or URL, there’s a nice hover-effect.

Humble

Humble is a simple, single column, green theme

Techy People

A three columns, fixed width, light weight, fast loading theme. Widget, adsense and gravatar ready, separate comments and trackbacks. Logo .psd included. XHTML and CSS valid, tested on Firefox, IE 6 and IE 7.

BlueShadow

Widget and gravatar ready theme with a featured last post, 5x ad on latest post and 5x ad on single post, custom pages, image-styling, nice graphics and a lot more.

Simple

Simple grey, white and blue, two column theme

M (removed due to sponsored links)

Adsense and widget ready, seven column, fixed width brown WordPress theme

Ubuntu WP

Three column, widget ready theme named after the popular operating system

Ellise (removed due to sponsored links)

Ellise is a 2 column theme, right sidebar position, widgetized and adsense ready.

PureCSS

PureCSS theme is a pure CSS WordPress theme, no image. The theme is compatible with latest WordPress, widget, valid CSS and XHTML, and has been tested with in Firefox, Internet Explorer 6 &, Opera, and Safari.

mts Gossip Rag

Gossip Rag is a simple, two column, localized, widget ready, fix width WP Theme for gossip or celebrities.

NYC Reds

Fluid four column outfit with news slider built into the frontpage, widgetized sidebar and footer columns with typical WordPress, built in are recent comments with gravatars, related posts, social bookmarking enabled.

Connections Reloaded

Connections Reloaded is a complete reload of the highly popular and extremely beautiful Connections theme by Patricia Muller. Connections Reloaded 2.0.1 is a two column, widget and Gravatar ready theme. Includes few inbuilt widgets as well as many page templates.

Ginseng Coffee

Ginseng Coffee is a three column, brown, widget and Gravatar and tag ready theme.

Floral Day

2 columns, widget ready, right side bar, with Ajax picture viewer enable

Simplest

A simple two-column WordPress theme with a small splash of color.

While on the topic of themes, you might like to take a look at Building with WordPress: From sketch to prototype to company website in 5 hours and Collapsing WordPress Widget-Ready Areas & Sidebars and Show latest comment(s) for each post on main page.