I have been using onenote a lot recently because of its collaboration features and because of its integration with outlook, communicator, windows, etc. Onenote is fun and easy to use; the power and simplicity of the hierarchical tabbed organization, and the "blank canvas" layout features make it better than MS-Office-Word for editing documents. You can drag the pictures anywhere on the canvas! Onenote enables quick and easy rectangle screen captures; it stores documents in pages more flexibly than the windows shell; you can "print" to a onenote page then strings(1) out the text. It enables collaboration with soft real-time sync/merge so that many people can work on the same notebook at the same time. In meetings anyone with wireless network can take over writing notes / minutes. At a conference you can read all the notes from all the sessions your team is taking.
I am forced to use more than one computer so I store my own notebooks on a desktop machine at work and create a share for them that only I can access. Then I use onenote's awesome offline and sync with auto-merge feature to access these notebooks on the laptop.
I recently read that onenote's sharepoint integration is actually just webdav. Therefore the free public Internet hosting services that support webdav can be used to store onenote notebooks. I did a little bit of experimenting with the free hosting services; box.net does not work for me, but frontpages-web-hosting.net does. Unfortunately the better, free "cloud storage" services such as omnidrive or streamload (25 GB free!) do note yet offer webdav access. I can imagine scenarios where having "cloud storage" of onenote notebooks and using pocket-onenote in a mobile phone would be very elegant and useful.