Online Storage

Wuala is a secure online storage, made in Switzerland. As the Swiss knife of online storage, it covers all the essential needs for professional and personal use: with Wuala, you can store your files securely online, share them with select others, access them from anywhere, setup automatic backups of your local data, or synchronize whole folders to the cloud. --Wuala.com

Description from Wikipedia
Mozy is an online backup tool created by Berkeley Data Systems, a Silicon Slopes company based in Pleasant Grove, Utah. The Mozy online backup service allows both Windows and Mac users to back up their data to an off-site server. While originally released as a product for end-users, Mozy later released a remote backup utility for businesses called MozyPro.

Mozy currently offers three versions of backup software: MozyFree, MozyHome and MozyPro.

Mozy Free allows users to back up as much as 2 GB of data from up to two computers (referring others to Mozy gives free users an additional 0.25 GB of storage space). MozyHome Unlimited allows unlimited backups from one computer. MozyPro is the business class version of the Mozy backup software.

Mozy has the ability to back up several types of files such as bookmarks, documents, and e-mails at once rather than forcing the user to select particular files or folders. Mozy also has the ability to back up locked files, such as the Outlook.pst file. This allows backup of files that are in use, offering users near-continuous protection against data loss.

description from Wikipedia
Dropbox is a storage application and service operated by Dropbox, Inc. The service enables users to store and sync files online and between computers.Dropbox has a cross-platform client (Linux for x86 and x86_64, Mac, Windows and the iPhone) that enables users to drop any file into a Dropbox folder that is then synced to the web and the users' other computers with the Dropbox client. Files in the Dropbox folder may then be shared with other Dropbox users or accessed from the web. Users may also upload files manually through a web browser.

A free Dropbox account offers 2 GB of storage. Users may upgrade to 50 GB or 100 GB by paying a monthly or yearly fee. The total amount of storage space of both the free and fee-based accounts may be increased by up to 3 GB for free accounts by increments of .25 GB and 6 GB for fee-based accounts by referring others to the service.