One of my favorite free web services is Dropbox. There are a number of free file sharing services available on the Internet, but none work as seamlessly as, or include the great features of, Dropbox.

At its base, Dropbox is a simple file sharing service allowing you to save files online (in “the cloud,” as the youth like to say). What makes Dropbox so powerful is how it syncs with your computer(s). Sure, you can use the Dropbox website to upload and download files, but you can also install a small piece of software that will allow Dropbox to integrate with your computer’s OS and create a Dropbox folder that remains synced with “the cloud.” Want to upload a file to Dropbox, drag it to the folder and it syncs. Have another computer, a laptop for travel, an Android phone or iPhone, or want access to your files at work? Install the Dropbox software on those computers and the files automatically sync everywhere.

The next great feature about Dropbox is that all your files are backed up. Accidentally delete one? No problem, log on to Dropbox and restore the file. Working on an important document? Make some changes and save the document, but now you want to go back to an earlier version? Dropbox has you covered – the backups include revisions. Pretty sweet! Backups and previous file versions are kept for 30 days.

Of course, it’s not a great file sharing service if you can’t share files. Drag any file into the “Public” directory and it will be available to others. You don’t have to worry about privacy, though, the directory isn’t listed anywhere. In fact, that’s the one downside – you can’t share an entire folder, just individual files. Of course, that’s easy to remedy, should you need to share multiple files, just zip the files you need to share into one.

Image galleries are a different story. Upload a bunch of pictures to a folder in the “Photos” directory and you can share a gallery with anyone you want. The images are resized into thumbnails and 640 pixel wide photos that are perfect for viewing online. The full size images are available for download and printing. This means there’s no need to resize all your images before sharing with your friends.

Of course, for me, it’s the Android app that has sinched it. With the Andorid app I can download any of my files to my phone anytime I need them. Or upload files to Dropbox for viewing later. This is great for saving room on the SD card. After making a nandroid backup I can easily upload the backup directory to Dropbox, and it’s immediately available next time I need it.

If you haven’t given Dropbox a try, go ahead and sign up for 2GB free storage. Plus, if you sign up through Jonamerica.com, you’ll get an extra 250MB of storage space – cool!