If you have been using dropbox.com for cloud storage, you may have heard they were recently hacked and your username and password may have been compromised. If you're seeking a more secure way of storing and sharing your files, check out SpiderOak.
Their biggest selling point is "zero-knowledge privacy", which means they have no idea what you are storing on their servers and no way of finding out.
SpiderOak provides military grade, end-to-end encryption; data in transit and being stored are fully encrypted using a password you select. The downside? If you lose or forget your password, you have also lost your files.