WP Glamour sell premium WordPress themes and offer some free themes for download.
A design company with a speciality in WordPress themes. They designed a custom theme for WordPress.com. Custom designs start from $2'000.
Sandbox is a generic WordPress theme with extensive CSS styling, etc, which can serve as the base for many theme designs.
Revolution is a commercial theme for WordPress. You buy the theme either as a single license or developer license for $80 - $400 USD (ast at Mar 2008).