Robin Good: Annotary is a free web bookmarking tool, which allows you to collect onto Pinterest-like visual boards, web pages that you have bookmarked matched with your specific text highlights on them.
From the official site: "Bookmark interesting or relevant pages into collections so you can easily find them later. Create as many collections as you want – one for each project, or one for each topic."
Free to use.
Try it out now: http://annotary.com/
(Thanks to Nick Peachey for uncovering this one)