If you're not already using Dropbox, we have to ask: What are you waiting for? This popular service lets you easily sync files between computers, share with them others, and create backups. Best of all, it integrates so seamlessly with Windows -- and other platforms -- that you're barely even aware that you're using it. This program is a must-have for anyone who needs to make their files readily available to multiple users or computers.
Once installed, Dropbox appears as an icon in the system tray. It doesn't have an interface, exactly; it turns up as a folder in My Documents, and it functions just as any other folder would. The magical thing about this folder, however, is that its contents are stored both locally and in the cloud. Any files or folders that you place inside the Dropbox folder can be easily shared: simply right-click, select Dropbox from the context menu, then select Share Link. This will open your default browser and provide you with the opportunity to share the selected file or folder via e-mail, Facebook, or Twitter, or to simply copy its Dropbox URL. The folder contents will also be automatically synced, so anyone who has access to a folder will immediately have the most up-to-date files. You can forget about using USB drives or e-mailing documents to yourself; Dropbox lets you keep everything you need in My Documents on multiple computers, or simply log into the Web interface if you're not on a machine that has Dropbox installed. Dropbox requires users to create an account; the service provides users with 2 GB of space for free, but paid upgrades are available if you need more. A thorough online Help center, as well as brief text instructions within the Dropbox folder, provide plenty of well-written documentation.
Dropbox is incredibly easy to use and will change the way you store and share files. We highly recommend it.