1.Free WP Themes at www.freewpthemes.net has currently over 200 different WordPress themes you can choose from.
2.Wordpress Themes Base at wordpressthemesbase.com has a collection that contains a great number of free WordPress themes.
3.themes.rock-kitty.net has also lots of great themes to choose from.
4.Top WP Themes at topwpthemes.com offers quality and professionally designed WordPress templates for free download.
5.Smashing Magazine made a list of the hundred coolest WordPress themes of the year 2009, last year they made a similar list. Go to www.smashingmagazine.com/2009 or www.smashingmagazine.com/2008 to take a look and you will surely find great themes for your own use also.
6.Themelab at www.themelab.com has over hundred different themes, all free for use.
7.Themes 2 WP at www.themes2wp.com has hundreds of quality WordPress themes.
8.Wicked WordPress Themes at www.wicked-wordpress-themes.com has also lots of themes available for free download.
9. WordPress Themes for Free at wordpressthemesforfree.com claims they are “biggest resource of WordPress themes” and you can browse through hundreds of WordPress themes.
10.Template Browser (www.templatesbrowser.com/wordpress-themes) also has some themes to offer but the search function isn’t as good as any of the other pages in this list.
11.Free Theme Layouts at www.freethemelayouts.com has only two categories (business and personal) but they both have number of quality free themes for download.
12.WP Theme Spot at www.wpthemespot.com has only few dozen free themes but it’s still worth checking out, especially if you don’t want to browse through hundreds of themes.
13.Wordpress Supplies at wordpresssupplies.com offers free WordPress themes.
14.Wordpress Themes at www.wpthemes360.com has over 2000 WordPress themes but it has now categories or now search field, only a randomize button, so going through all those beautiful themes is really hard work.