I just found a New WordPress theme site freethemelayouts.com. In this site you can search many collection of wordpress theme. This wordpress theme is diferent from other wordpress theme collection site. Usually, in other wordpress theme site, when you want to see the theme or the implementation of a theme you should go to the demo preview page, but in freethemelayouts you just need to move your mouse pointer to which the theme you want to see the preview. When you move your mouse to one of the thumbnails a big preview of the theme will apear. Howefer if you want to see the implementation of the theme in a wordpress site, there is also a demo page available just like in a usual wordpress theme site. You can also directly download the theme from the homepage or main page, you do not need to open every wordpress theme page because in each theme they displayed, they also put the direct download link at the bottom of every theme. On every single page, they display up to 30 theme directly with the demo link and download links.
Freethemelayouts has a complete collection of free wordpress themes. They collection is also great, there are many cool wordpress them that can be download directly. I, myself, have download many wordpress theme from this site. Although, I do not use all of the theme I downloaded.
If you need a new theme for your WordPress instalation you can try to find one from this site. Or maybe you recently upgrade you wordpress instalation to WordPress 2.7, in this site you can also try to find the new version of wordpress theme that compatible with WordPress 2.7.You can also subscribe here to get this site update in your email.