Before you head off into "The Cloud," plant your feet firmly on the ground and figure out how to protect yourself and your data from legal and privacy threats as well as technological snafus, outright failures and other interesting occurrences.

As you’ve likely noticed, Cloud computing is the newest big idea that’s going to magically solve all our “pain points” -- that’s a marketing department term for the things that drive you insane with frustration. The annoyances that you can appease by wrapping yourself in a puffy white computing cloud include, lack of easy access to your stuff when you’re using various computers and devices, and problems encountered when sharing your stuff with others.

But for every problem solved by technology, another problem is created. When you use Cloud-computing applications like Web mail, iDisk and Google Docs, the program and your data don’t live on your local hard drive, they’re stored somewhere out there on the service provider’s hardware. The way it’s supposed to work is that you and your chosen others can effortlessly access this data from any compatible device, using a web browser, whenever desired.

It all sounds so swell … until those puffy white clouds turn dark and a hard rain falls on our happy little ethereal computing wonderland. The mail service goes down, the service provider goes out of business, somebody hacks something and your personal data is stolen, etc.

And there are some ominous thunder rumbles from the legislative branch of the US government stating that any data you have stored in The Cloud may not be as private as you might expect. By placing it in a venue where you, so say some legislators, had no expectation of privacy, you’re also entitled to less legal protection than you would if you kept that same data safely tucked away on your own personal computer. For a more detailed discussion of how privacy and The Cloud might work, there’s a useful post on the University of Chicago’s Law School Blog.

In general, e-mail isn’t ever the best way to conduct discussions about clandestine or criminal activities. Should you need to consult with your partners in crime, and you really want to do so using email, consider restricting those exchanges to a private, paid non-webmail account -- a recent court ruling (Warshak v. United States) indicates you have more expectations of privacy in a legal sense when you aren’t using remotely stored e-mail. Preferably, anything that you wouldn’t print on the back of a postcard should be encrypted when sent in email -- if that’s too much of a hassle, pick up a phone. And do resist any bizarre inclinations you may have to use Cloud services to back up documentation of your illegal, or super-secret activities.

And while it’s not likely that any of the big webmail services will go out of business tomorrow, a quick glance at the latest headlines demonstrates that we’re living in strange financial times. If losing the e-mails (and contact information) stored in a webmail account would cause you financial or emotional harm, back ‘em up. Apple provides mail backup instructions for the obviously-cursed-by-an-evil-stepmother-at-birth MobileMe service here, Gmail instructions are here. For Hotmail, you can download MacFreePops and use it to move Hotmail messages into Mac OS X Mail. If you use Yahoo mail, you’re out of luck in the backing up department unless you spring for Yahoo Mail Plus at a cost of $19.99 a year.

If you’re backing up data into the cloud, first read the privacy policy of the hosting company (yes, you really have to, sorry) to make sure they don’t claim rights over the data stored on their infrastructure. Send them an e-mail if there are any stipulations that you don’t understand and ask for clarification. Be aware that policies change whenever our corporate overlords find a new way to make a dime, so re-check the policy periodically. And think hard about storing critical or highly personal data anywhere that is not under your personal control.

All that said, good backup practices dictate that we should have a redundant copy of our most important data in a remote location, far away from the floods, fires, and other hellish events that might make Backup A inaccessible. If your livelihood depends on your data, backing up onto a remote cloud server like Amazon’s S3 service using Jungle Disk, may be your best option. Jungle Disk encrypts stored data, if you choose a service that doesn’t do so check out TrueCrypt for a great encryption solution.

Synching in the Cloud can be a security issue, especially if services don’t provide a way to encrypt the data when it’s on their servers or being transmitted to their servers. Numerous investigations by security experts (Google “Privacy and MobileMe”) indicate that MobileMe does not encrypt data while it is in transit. Use it on an unsecure connection like public wireless and your data can be snagged by anyone in the vicinity with basic hacking skills. Depending on what sort of information you’re synching this could be an issue -- your contacts, bookmarks and calendar? Likely not a big deal. Anything with passwords, financial data and other personally identifiable information that you’d prefer to be kept private shouldn’t ever be sent over wireless connections unencrypted, obviously.

None of this is rocket science. Wireless connections are notoriously insecure, corporations don’t always have our best interests in mind, governments make wacky laws, and logic tells us that having only one copy of any important data is tantamount to taunting the gods of technology. But practicing safe and sensible computing will go a long way in ensuring that your data is secured from technological traumas here on earth or in the Cloud.