Evernote is an interesting combination of the old and new -- if you consider "old" being a desktop client, and "new" being a Web-based app. It lets you clip information from any application on your PC in a variety of media forms -- Web pages, emails, images, videos, documents, whatever -- and create a series of "notes." An icon in your Quick Launch bar lets you save anything on your desktop; you can also put an icon on your browser toolbar.
The info, once gathered, can be categorized and/or tagged. You can then either browse through your Evernote notes, do a search, or find it by clicking on the category and/or tag.
I tried two iterations of the application: Evernote for the Web and Evernote for Windows (it's also available in Mac and mobile versions). The Web version, of course, makes it possible to access your notes on almost any machine; it syncs nicely with the desktop client (either automatically on a regular basis or manually). It is more limited than the desktop version in number of features (not surprisingly), and needs a bit of work; for example, the Save Changes button also takes you out of edit mode, which is frustrating for those of us who live by the "save often" philosophy.
As a result, I began working with the desktop client as a standard, and using the Web version when I needed to. And so far, I'm very impressed; while my personal jury is still out as to whether this will really tame my rather nasty info glut, it looks like it may actually work. I've been able to, for example, drop bits of info about new products and sites into Evernote, and then browse them to see what I should investigate next.
And there are a lot of interesting features in there that make you want to really dig around in the application. A good example: the ability to do a search on text within images. You can, for instance, snap a photo of a document, send it to Evernote (you can email data to your account) and then do a search on the words within the document. (The image is processed by Evernote's servers, so if you place an image in your desktop client, you need to sync it before you can do the search.)
Evernote is currently in a sort-of-private-beta -- you need to register to use it, and registration is offered either by invitation (each user gets 20) or by emailing the company. I received an invitation to register about 24 hours after requesting one via the Web site. According to the company, when Evernote goes out of beta, there will be a free version and a premium paid version which will offer "higher quotas" -- in other words, the free version will most likely have some limits on content.
Still, for now, Evernote is a real find for those of us who are information packrats.