Dropmark is a nice way to collect and share stuff, were stuff can be webpages, images, files, text, links etc. Each piece of stuff is thumb-nailed. Clicking on a thumbnail opens it on the screen and you can arrow-key through the collection. collections can be private, public or shared. You can collaborated with others.
You have 250 MB free storage space. There is a safari extension (and firefox add-on) that opens a side bar on a webpage and allows you to drag and drop urls (where the whole page is captured), images or blocks of text. You can drag files from your desktop too.
Clicking on the thumbnail above will take you to a quick example Gif Animation is a mix of images from the web, webpages and files from my desktop. EDUhack is a collection of links.
Video Test is a mix of Vimeo and Youtube videos, dragging the url dropmark thumbnails the videos and clicking on the thumb plays them browsers window size.
Using dropmarks is pretty intuitive, but there are plenty of written and video instructions on Dropmark®.
Finally each collection has an RSS feed which mean you could quickly put together a podcast of disparate materials. and there is an API in the works.