Avirb Motion is a 3-column, widget-ready theme that has the ability to highlight author comments.
FTW is a 3-column, theme with a black background and icons from famfamfam.
Geezeo is a 2-column, simple theme with gravatar support.
Loopy Blue is a 2-column, widget theme with blue colors.
Nature is a 3-column, widget-ready theme with a magazine-style layout.
Particles is a 4-column, portal-style theme is designed to be extremely lightweight, easy to build upon, and extremely fast for all browsers.
Photo Blog is a simple and clean photo blog theme.
Vertigo is a 2- or 3-column, widget-ready theme.