'Onfolio is the most useful .NET client app that I've seen so far. As I surf around I drag things into my list. Then I can right click and do a whole bunch of things. I can create a web page/report for my team (or, for other important people). I can email them around. But, it lets me stay organized as I go around the Web. It really is like a Favorites list on steroids.' Scobleizer
Onfolio is a PC application for collecting, organizing and sharing information you find online. Fully integrated with Microsoft Internet Explorer and Office, Onfolio has tools for capturing a wide range of content including links, text snippets, images, web pages, and documents. Onfolio lets you organize and find captured content quickly and easily. And with Onfolio, you can easily share your research in documents, presentations, emails and research reports.
Update (19.3.2004): see reviews of Onfolio posted on Marc's Outlook on Productivity and a review by Walter Mossberg in Personal Technology.

