Microsoft's Live Mesh

One of the most successful tools I used this past academic year is Microsoft's Live Mesh ( https://www.mesh.com ), a cloud-based file-synchronization and desktop-replicator. I had signed up for it when it was in Beta and have never had a problem with it; in fact, it's worked far better than the Sharepoint system that the school offers. It installs as a service onto your Windows computer and creates a small blue icon that flashes when it's synchronizing.
Since we use OneNote for all of our academic material, it is nice to be able to access your Notebooks from any computer. With LiveMesh, I store the notebook in the LiveMesh folder (which appears to the computer as any other folder) and open it in OneNote as usual. I can work with OneNote, adding, editing and deleting and while I'm working away LiveMesh is synchronizing the local copy on my computer with the copy on the cloud which is also syncing it with any of my other computers (one tablet, one laptop). If I need to use the files on a computer that isn't mine, I can access the files through any web browser, too.
Not only do I store all my OneNote files in a LiveMesh folder, I store all my day-to-day academic files in one. I also have folders for my action research, journal writing, e-textbooks and backups. There have been a few times in the past I will be using my desktop to create school work and forget to upload it to the web for use at school -- by putting it in a LiveMesh folder, it's automatically available to me. If my laptop fails, my files are safe. Even if LiveMesh or the network is down, the local copy is useable.
There are two other things that are nice about LiveMesh: first, you can share the folders with other LiveMesh users. I've done this to distribute large files to my AP Calculus students and to have my Advisor Group do their backups in case their laptops fail. I've also used it to work with colleagues across the country; no need to email files back and forth (normally I'd suggest GDocs for this but not everything is a document/spreadsheet.)
The second is that you can actually log into your remote computer that is running the LiveMesh service. I've used this several times when I'm running a task on my desktop at home that I want to check on or continue with while I'm at school. I don't always leave my home computer on (they use a lot of hydro, after all) but it has turned out handy if I have to work in two places at once.