For all you visual learners out there, VisWiki is for you. I heard about VisWiki from VerySpatial and this wiki site is really rich with search capabilities. Here's what VisWiki has to say for itself:
VisWiki is a visual, intuitive, and interactive web interface to encyclopedic knowledge/information, especially of Wikipedia. It is designed to provide a fun place to learn stuff in an efficient manner.
Above you can see the different pre-configured categories (expand the plus sign to find out sub-categories) and the languages you can search in. Below I did a search of "tablet PCs" to see what they came up with.
At green #4 shows that there are 674 videos related to 'tablet PCs' and if you want to search further and link off and out of this VisWiki page, at green#5 you can search Flickr or YouTube or Yahoo, and so on.