There are two main online backup services: Mozy and Carbonite. Both offer a similar service: they upload files differentially and incrementally (as they are updated or made) to a server and those files can then be retrieved. Both are now also available for Windows and OS X. Prices are similar, although Mozy does offer users 2GB free of charge.

Carbonite offers a 15 day free trial, where you don’t even have to input your credit card information. This, like a regular subscription, allows you an unlimited amount of storage. Unlike a paid user, free trial users can’t upload music or movies, quite understandably. Paid users have no issue though.

I personally use Carbonite, but wouldn’t advise anyone against Mozy. Carbonite was quite simple to set-up, my only complaints are that it didn’t automatically configure the OS X firewall or my ports and a few minor user interface issues. I expect that it is much more polished on Windows, as their OS X version is a recent release.

Carbonite also provide remote access, so you can access your backed up files anywhere. This is useful if you need a file off your home PC at work, for example.

Uploading is fairly fast. After I configured my firewall and ports correctly, I managed to get a couple of gigabytes uploaded in one night. That is impressive considering I’m on a relatively slow (2Mbps downstream) ADSL2 connection.

Carbonite’s customer support solved any of my problems but I felt a lot of the dialog was scripted and for some reason it all seemed a little impersonal. Still, they provided me with solutions in a reasonable timeframe in a courteous manner.

Now, pricing. Carbonite is $55/year and Mozy (for home users) is $4.95/month. However, it is possible to easily save 20% on this through using Subscription.com . A couple of extra clicks can save $11 on Carbonite and 15% on Mozy. Go through this page for a Mozy and Carbonite offer code. I did this and found it a remarkably easy process.

Disclosure: Subscription.com reimbursed my purchasing a Carbonite licence under the condition that I reviewed it on my personal weblog. I was in no way required to show bias or blog about Carbonite on gHacks, I simply chose to as it’s a good service.