An online collection of reviews of nude scenes in many movies performed by many actors and actresses.
If you've ever wondered whether your favorite actor or actress has appeared nude, topless, or bottomless in a movie or show, the site at http://www.cndb.com/ might be able to satisfy your curiosity.
Searches can be done by actor/actress and by movie; the reviews are sometimes very good (telling you precisely what timestamp into the movie the nudity occurs, what's seen, etc.), while others are clearly written by ten year olds.
Still, there's something oddly satisfying in discovering an actress you're fond of has done dirty nekkid things. It's information many would rather we all forget, but thanks to sites like this, that's unlikely.
Roughly one year ago the site was down for a prolonged period of time (several months), while work was done to integrate the site into "Mr. Skin"'s site. Mr. Skin is similar to the CNDB, except it's a pay site with still and video captures of the nude scenes (useless if you have a decent USENET feed). The transition was a mixed blessing; the site is faster now, but naturally has lots of ads for Mr. Skin's site.
The site's owner appears not to have updated anything for several months, but individual users still make frequent contributions (moderation isn't required, so reviews are added instantly).