Snap.com is not only a search engine, but plays host to one of the coolest pieces of web technology for bloggers and web developers of all kinds. Their SnapShots application is a great tool which can easily be embedded on your website to display external content right on your page without the user ever leaving.
You can use Snap to display video, images, Wikipedia info, RSS feeds, MySpace profiles and of course web site previews to name but a few.
I personally have used this great web application for several development projects to display video and external links in-line on some niche websites and blogs. If you think about it any one of the SnapPreview features provided could be used for a unique development project. With all the new features and options being released soon I will definitely be considering developing some of my domains using some of the new features to provide rich and relevant media to website visitors.