SpiderOak, based in Illinois, offers 2GB of free online storage, which should be enough for the mission-critical documents you need to sync across devices. If your storage needs are larger, try Switzerland-based Wuala, which offers 5GB free.
Both services provide back-up and Dropbox-like functionality. SpiderOak's Hive sync sits on your PC as a special folder, while Wuala syncs to your PC as a network drive.
As is true of any online secure service, you have to be comfortable with the company and trust that the service is doing what it claims it is to keep your data secure.
Secure your online services with two-factor authentication
The first line of defense for keeping your online services secure is to use unique, random, passwords of ten characters or more for every account you have--just don't forget to store them in a good password manager. For even better security, turn on two-factor authentication for Google, Facebook, and every other service that offers it.
Two-factor authentication requires you to enter a short numeric code in addition to your password before you can gain access to your account. The code usually comes from a physical fob or from a smartphone application. The good news is that you can get most of your two-factor authentication codes from Google's Authenticator app for Android and iOS.
Authenticator automatically works with accounts such as Dropbox, Evernote, Google, LastPass, and Microsoft. Facebook offers its own code generator inside the social network's mobile app, but you can add Facebook to Authenticator as well. From the Facebook newsfeed, click the settings cog in the upper right corner and select Account Settings.
On the next page, click Security in the left-hand navigation column. Under 'Security Settings' look for the 'Code Generator' menu option and click Edit to the far right of that option.
Click the link in the first two words of the sentence Set up another way to get security codes.
A QR code should appear in a pop-up window. Open Authenticator, navigate to the 'Add Entry' option, select Scan Barcode, and point your phone's camera at the QR code on your monitor. In a few seconds, your phone will identify your Facebook account code and add it to Authenticator. Enter a Facebook code from Authenticator to ensure that everything's working properly, and you're done.
Two-factor authentication isn't foolproof, but it does add a hurdle to help deter anyone who wants to get into your account. Twitter offers its own two-factor authentication, but its method is not compatible with Google's Authenticator. The last time we checked, Twitter's authentication method still had some kinks to work out.
If two-factor authentication isn't enough security for you, take stock of the backup email address you use for all of your online accounts. Consider using one or several unique email addresses as password recovery addresses. Just make sure that you never give out these email addresses for personal mail and that they aren't similar to your other accounts.
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