From the Web 2.0 Conference:
Stikkit is like an online pad of yellow sticky notes. These notes, though, do more than the pieces paper you scrawl notes on and then lose. Stikkit tries to interpret what you mean when you write stuff like, "Call Mary at 4pm tomorrow," and then organize your notes for you. In that particular example, it will file the note as an appointment.
Stikkit has a grammar for doing other smart things, and it does take a few minute for a user to learn it. For example, to-do items are created when you preface an item with "todo:" or "-". But just writing, "Call Mary tomorrow," won't do the trick.
Stikkit will create a "peep" (person) record whenever it sees what it reads as a name (first and last), which makes it very easy to quickly save a person's phone number or address and easily recover it later. You can use a browser bookmarklet to save Web pages, or just type in a domain to autofile something as a Web bookmark.
All notes can be tagged (you just write "tag as x"), and later you can quickly find items by tag. You can also share notes with other individuals.
There are several online note-grabbers, and almost all PIMs, both Web-based and standalone, enable you type and save notes. But Stikkit's rudimentary intelligence (which reminds me of the pre-Web PIM, Agenda) and elegant design (which is very Web 2.0--simple and big) sets it apart from most of them. It really is simple and easy to use. Its language skills need improvement, though. It's too easy to confuse Stikkit, and it's too hard to correct it when it misfiles a note. But the app is in beta, indicating that there is a lot of potential here.
Stikkit is a standalone application right now. It won't send contacts, appointments, or to-dos to your PIM, which would make it much more useful. But the team is working on building conduits to popular programs and sites. Likewise, Stikkit bookmarks may soon be exportable to Del.icio.us.
See also the updated version of Posticky [review of previous version], an online corkboard of sorts. Posticky's notes aren't as smart (or as pretty) as Stikkit's, but the service enables you to save sticky notes on any Web page, via a bookmarklet. MyStickies is another service that lets you paste personal sticky notes on the Web pages you visit. And keep an eye out for Stickis, which uses the sticky-note metaphor for social and collaborative browsing; I plan to review it soon.