My current remote backup solution is JungleDisk. Since it's one that I use and am familiar with, I figured it'd be the first review I do. There are other solutions out there, but I think JungleDisk will fit most people's needs the best.

Features

JungleDisk is a front end application to Amazon.com's S3 service. Amazon's S3 remote storage runs on Amazon's many servers and features redundant backups in multiple locations and a very cheap price. JungleDisk has two main uses; as an automatic incremental backup and as a remote hard drive.

JungleDisk's main feature is a automatic backup of the files on your computer. You can set up which directories and files get backed up and how often. You can also restrict certain file types from being backed up, like MPG files or files that end in .bak. During the backup run, JungleDisk will only upload files that have changed since the last backup. This saves on the time it takes to run the backup and helps you save money, since you have to pay for the amount of data transfered to and from S3.

JungleDisk also mounts the remote file system onto your computer, allowing you to use your JungleDisk bucket as if it was a local hard drive. With this, you can see all the backup files and recover them if needed. You can also use S3 as a remote storage unit of your own, dragging and dropping files into the S3 bucket, bypassing JungleDisk's scheduled backup features if you want.

To me, one of the killer features is that JungleDisk allows you to set an encryption key for your files. This means that the only person who can read your backup files is you. JungleDisk won't have access and Amazon won't have access. Only someone with the key that you set will be able to view the files. You'll have to protect your key in case your computer crashes and you have to recover your files, but no one who gets your files from Amazon will be able to see them.

Pricing

JungleDisk is a steal at only $20 with lifetime upgrades. I have never seen a computer program so useful yet so cheap in my life. You can also try it for 30 days to see if you like it. If you don't, just delete the S3 account from Amazon and uninstall JungleDisk. You'll only pay the Amazon S3 fees for that month.

There is also a Plus service that is designed to help you save money if you back up very large files. It costs $1 a month and is designed to help people that backup up very large files by caching parts of those backups on JungleDisk's servers. I don't backup very large files, so I haven't tried this service.

Even though I don't pay a monthly fee to JungleDisk, I do have to pay S3 for storing my files. I currently keep about 5GB of data on S3 between two computers with nightly backups. This has ended up running me about $1.20 a month, which is nothing compared to the piece of mind JungleDisk has given me. You can check the Amazon S3 Calculator for what your monthly price might be. Keep in mind that the Storage is the amount of data your saving, Data Transfer-in will be the amount of changed files in a month, Data Transfer-out will be the number of files you recover in a month (should be zero), PUT/LIST requests are done when checking the cached files against your current files. PUT/LIST requests are the hardest to estimate, but mine are at about 15,000 a month. From that, you should be able to estimate your usage and what your monthly fee might be. Remember that, for the first month, your Storage and Data Transfer-in numbers will be the same, but every month after that Data Transfer-in will just be the size of new/changed files.

Future Worries

My only real worry is that JungleDisk was recently bought by Rackspace. Rackspace recently announced a cloud storage of their own which competes with S3. I really like S3's pricing and service and would hate to have to switch, but there have been a couple of reassurances by JungleDisk's author that S3 will stick around as an option, which makes me feel better.

I have a cheatsheet in the works for JungleDisk and will be posting it soon. For now, I recommend installing it, getting an Amazon S3 account and setting up a quick backup of your most important files.